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Aluminum is the most abundant and promising material for hydrolytic hydrogen generation. It can be easily transported and stored. However, the oxide protective layer around Al limits its hydrolytic activity and hinders practical applications. To solve this problem, NaH is introduced to form the core-shell structure of Al-based NaH solid fuel powder by a simple hand mixing method in an open lab environment. The new core-shell structure of Al-based NaH solid fuel powder showed the best hydrolytic performance among Al-based materials and produced 98 % hydrogen yield at a 1 to 0.9 M ratio of NaH and Al in water. The hydrolytic activity consists of NaH hydrolytic splitting and Al hydrolysis. XRD and SEM analysis confirmed that NaH is the key to supporting complete Al hydrolysis and attaining maximum yield as compared to calcium hydride. Our research endorsed the practical implementation of inexpensive and transportable hydrolytic hydrogen generation materials and offered a new idea for the design of hydrolytic hydrogen generation materials for further development. [Display omitted] • Aluminum-based sodium hydride is cheap and transportable hydrogen generation material. • Aluminum hydrolyzes completely in the presence of NaH and produce 98 % yield. • Applicable for affordable hydrogen delivery systems to movable electronics devices. [ABSTRACT FROM AUTHOR]

Recently main group compounds have stepped into the territory of precious transition metal compounds with respect to utility in the homogeneous catalysis of fundamentally important organic transformations. Inspired by the need to promote more sustainability in chemistry because of their greater abundance in nature, this change of direction is surprising since main group metals generally do not possess the same breadth of reactivity as precious transition metals. Here, we introduce the dihydropyridylsodium compound, Na-1,2-tBu-DH(DMAP), and its monomeric variant [Na-1,2-tBu-DH(DMAP)]·Me6TREN, and demonstrate their effectiveness in transfer hydrogenation catalysis of the representative alkene 1,1-diphenylethylene to the alkane 1,1-diphenylethane using 1,4-cyclohexadiene as hydrogen source [DMAP = 4-dimethylaminopyridine; Me6TREN = tris(N,N-dimethyl-2-aminoethyl)amine]. Sodium is appealing because of its high abundance in the earth's crust and oceans, but organosodium compounds have been rarely used in homogeneous catalysis. The success of the dihydropyridylsodium compounds can be attributed to their high solubility and reactivity in organic solvents. Organosodium compounds are appealing sustainable alternatives to precious transition metal compounds, yet they have rarely been used in homogeneous catalysis. Here, the authors introduce a dihydropyridylsodium compound, Na1,2-tBu-DH(DMAP), and its monomeric variant [Na-1,2-tBuDH(DMAP)]·Me6TREN, and demonstrate their effectiveness in transfer hydrogenation catalysis of a representative alkene, 1,1-diphenylethylene, using 1,4-cyclohexadiene as a hydrogen source. [ABSTRACT FROM AUTHOR]

Herein we report a method for the synthesis of thioethers by forging C(aryl)‐S bond via an aryne mechanism. The active aryne species can be generated from o‐diiodoarenes and NaH in THF at room temperature, then lead to the arylations of a wide range of aryl thiols and thioureas. Different from transition metal‐catalyzed cross‐coupling reactions, no disubstituted byproduct is formed in our protocol. The o‐iodoaryl thioether products are intermediates that could be transformed into pharmaceutically interesting molecules. [ABSTRACT FROM AUTHOR]

The reactions of dimesitylphosphane oxide Mes2P(O)H with Lawessons reagent and dimesitylphoshane with selenium yield Mes2P(E)H with E = S (1a) and E = Se (1b), respectively, with moderate yields. Metalation of dimesitylphosphane sulfide 1a with n-butyllithium, sodium hydride or potassium hydride in THF allows the isolation of dinuclear dimesityl-thiophosphinites of the type [(thf)2A-S-PMes2]2 [A = Li (4), Na (5), K (2a)] with central four-membered A2S2 rings. The weaker base THP leads to the very similar aggregate [(thp)2K-S-PMes2]2 (3a) as has also been observed for the homologous potassium dimesityl-selenophosphinites of the type [(L)2K-Se-PMes2]2 [L = thf (2b), thp (3b)]. Addition of 18-crown-6 ether leads to deaggregation and expectedly to formation of mononuclear [(18C6)K-S-PMes2] (6). Moderate yields have been obtained due to dismutation reactions that yield the corresponding phosphinates AE2PMes2 and phosphanides APMes2, a degradation process which has been observed earlier also for Li-O-PMes2. This side reaction hampers the application of these thio- and selenophosphinites as catalysts in the addition of phosphane sulfides and selenides across alkynes. [ABSTRACT FROM AUTHOR]

The reactions of dimesitylphosphane oxide Mes2P(O)H with Lawessons reagent and dimesitylphoshane with selenium yield Mes2P(E)H with E = S (1a) and E = Se (1b), respectively, with moderate yields. Metalation of dimesitylphosphane sulfide 1a with n-butyllithium, sodium hydride or potassium hydride in THF allows the isolation of dinuclear dimesityl-thiophosphinites of the type [(thf)2A-S-PMes2]2 [A = Li (4), Na (5), K (2a)] with central four-membered A2S2 rings. The weaker base THP leads to the very similar aggregate [(thp)2K-S-PMes2]2 (3a) as has also been observed for the homologous potassium dimesityl-selenophosphinites of the type [(L)2K-Se-PMes2]2 [L = thf (2b), thp (3b)]. Addition of 18-crown-6 ether leads to deaggregation and expectedly to formation of mononuclear [(18C6)K-S-PMes2] (6). Moderate yields have been obtained due to dismutation reactions that yield the corresponding phosphinates AE2PMes2 and phosphanides APMes2, a degradation process which has been observed earlier also for Li-O-PMes2. This side reaction hampers the application of these thio- and selenophosphinites as catalysts in the addition of phosphane sulfides and selenides across alkynes. [ABSTRACT FROM AUTHOR]

It is of interest to develop wide-temperature domain damped hydrophobic materials. In this paper, we designed incorporating bio-based phenolic resin into the IIR matrix and introducing dibenzyl fork acetone (DBA) into the main chain structure with sodium hydroxide activation to construct three-dimensional network. In this paper, we designed incorporating bio-based phenolic resin into the IIR matrix and introducing dibenzyl fork acetone (DBA) into the main chain structure with sodium hydroxide activation to construct three-dimensional network. The added bio-based phenolic resin has reticulated structure blended with butyl rubber, combined with sodium hydride activation-modified IIR. The results show that sodium hydride activated modification of DBA is introduced into the main chain structure of IIR by infrared and 1H NMR analysis. The material hydrophobic is realized by the introduction of DBA with static water contact angle of 103.5°. The addition of 10phr lignin-based phenolic resin (LPF) is compatible with IIR, and the torque can reach 7.0 N-m. The tensile elongation of the modified butyl rubber composite can reach 2400% with tensile strength up to 11.43 MPa, while the damping factor can reach 0.37 even at 70 °C. The thermal stability of the composites is enhanced with mass retention rate of 28%. The bio-based PF/NaH activation-modified butyl rubber damping material has potential applications in damping hydrophobicity with wide temperature range. [ABSTRACT FROM AUTHOR]

The nitrogen isotopic composition of nitrogen oxide (NOx) is useful for estimating its sources and sinks. Several methods have been developed to convert atmospheric nitric oxide (NO) and/or nitrogen dioxide (NO2) to nitrites and/or nitrates for collection. However, the collection efficiency and blanks are poorly evaluated for many collection methods. Here, we present a method for collecting ambient NOx (NO and NO2 simultaneously) with over 90% efficiency collection of NOx and low blank (approximately 0.5 μM) using a 3 wt% hydrogen peroxide (H2O2) and 0.5 M sodium hydride (NaOH) solution. The 1σ uncertainty of the nitrogen isotopic composition was ± 1.2 ‰. The advantages of this method include its portability, simplicity, and the ability to collect the required amount of sample to analyze the nitrogen isotopic composition of ambient NOx in a short period of time. Using this method, we observed the nitrogen isotopic compositions of NOx at the Tsukuba and Yoyogi sites in Japan. The averaged δ15N(NOx) value and standard deviation (1σ) in the Yoyogi site was (−2.7 ± 1.8) ‰ and in the Tsukuba site was (−1.7 ± 0.9) ‰ during the sampling period. The main NOx source appears to be the vehicle exhaust in the two sites. [ABSTRACT FROM AUTHOR]

The nitrogen isotopic composition of nitrogen oxide (NOx) is useful for estimating its sources and sinks. Several methods have been developed to convert atmospheric nitric oxide (NO) and/or nitrogen dioxide (NO2) to nitrites and/or nitrates for collection. However, the collection efficiency and blanks are poorly evaluated for many collection methods. Here, we present a method for collecting ambient NOx (NO and NO2 simultaneously) with over 90% efficiency collection of NOx and low blank (approximately 0.5 μM) using a 3 wt% hydrogen peroxide (H2O2) and 0.5 M sodium hydride (NaOH) solution. The 1σ uncertainty of the nitrogen isotopic composition was ± 1.2 ‰. The advantages of this method include its portability, simplicity, and the ability to collect the required amount of sample to analyze the nitrogen isotopic composition of ambient NOx in a short period of time. Using this method, we observed the nitrogen isotopic compositions of NOx at the Tsukuba and Yoyogi sites in Japan. The averaged δ15N(NOx) value and standard deviation (1σ) in the Yoyogi site was (−2.7 ± 1.8) ‰ and in the Tsukuba site was (−1.7 ± 0.9) ‰ during the sampling period. The main NOx source appears to be the vehicle exhaust in the two sites. [ABSTRACT FROM AUTHOR]

A method for the hydroalkylation of 1,1‐diarylalkenes has been developed using magnesium hydride (MgH2) generated in situ by the solvothermal treatment of magnesium iodide (MgI2) with sodium hydride (NaH) in ethereal solvents. The process is initiated by the hydromagnesiation of 1,1‐diarylalkenes with MgH2 to generate 1,1‐diarylethylmagnesium species, which are immediately alkylated with ethereal solvents to construct a diaryl quaternary carbon center in the hydroalkylation products. [ABSTRACT FROM AUTHOR]

The thermal management of the hydride based hydrogen storage reactor is the key factor to realize the complete storing potential of hydrides. In this regards a hydride reactor filled with sodium alanate in multiple tubes is numerically analyzed for absorption process. Based on various governing equations, a mathematical model of hydride reactor is developed and validated with the help of ANSYS Fluent. The hydride reactor uses mainly water or oil for heat exchange during hydrogen sorption. In the present study conventional heat transfer fluid (HTF) is replaced with the nanofluid since it has a greater heat exchange properties. The CuO/HTF, Al 2 O 3 /HTF and MgO/HTF nanofluids are selected based on previous studies and results of numerical experiment are recorded. The outcomes are attained for various parameters such as material and concentration of nanoparticles, supply pressure of hydrogen and inlet temperature of heat exchange fluid. The CuO/HTF nanofluid with concentration of 5 vol% exhibited better rate of absorption in comparison with other vol% concentrations and other selected nanofluids. It shows improvement in hydrogen absorption time up to 14% under selected conditions. Additionally, it is observed that CuO/HTF nanofluid with 5 vol% concentration is thermodynamically superior to other selected nanofluids; as a result it enhances the rate of the heat exchange up to 10% for hydride reactor. It is realized that the performance of CuO/HTF nanofluid with 5 vol% concentration is superior among picked nanofluids. Therefore for the hydride reactor the use the nanofluid is advantageous. • Developed and validated mathematical model of sodium alanate based hydride reactor. • Used nanofluid as a heat exchange fluid. • Presented performance for Al 2 O 3 /HTF, CuO/HTF and MgO/HTF Nanofluids. • Absorption time is improved by 14% for given conditions. • Reported up to 10% enhancement in the heat exchange rate for CuO/HTF nanofluid. [ABSTRACT FROM AUTHOR]

An efficient heterogeneous copper(I)-catalyzed cross-coupling of aryl iodides and pinacolborane has been developed. The reaction proceeds smoothly in THF at room temperature by using 10 mol% of MCM-41-anchored NHC-copper(I) complex [MCM-41-NHC-CuI] as catalyst and sodium hydride as base and provides a general and practical route for the synthesis of a wide variety of arylboronates in good to high yields. This heterogenized copper(I) catalyst can be facilely prepared via a simple two-step procedure starting from easily accessible and inexpensive reagents, and exhibits a higher catalytic activity than CuI and can be recycled more than ten times without any significant loss of its catalytic activity. [ABSTRACT FROM AUTHOR]

A new alkyne functionalized pterin derivative was synthesized through a reaction of 7-chloropterin with propargyl alcohol in the presence of sodium hydride. The purity and chemical structure of the compound was validated by NMR (1H, 13C) spectroscopy, Mass (APCI source) spectrometry, elemental analysis, and X-ray crystallography. The title compound may be further functionalized by exploiting the yne moiety, for instance, using click chemistry. The novel pterin derivative, most notably, in contrast to typical pterin behavior, is now soluble or even well soluble in almost any solvent except water. [ABSTRACT FROM AUTHOR]

An effective method has been developed for the synthesis of 2-amino-4-aryl-6-chloropyridine-3,5-dicarbonitriles from 3-arylcyclopropane-1,1,2,2-tetracarbonitriles by treating the starting materials with sodium hydride in anhydrous DMF, followed by HCl in isopropanol. [ABSTRACT FROM AUTHOR]

The development of alternative approaches to the conventional Haber–Bosch ammonia synthesis process is an imperative but very challenging task. Extrinsic stimuli such as plasma could provide greater flexibility in materials selection and process innovation for nitrogen fixation. Hydride (hydrogen anion, H‾)‐containing materials have recently shown promise in thermal ammonia synthesis, whereas the interactions of hydrides and N2 under plasma have rarely been investigated. Herein we explore plasma‐driven nitrogen fixation to NH3 mediated by an inexpensive and common reagent sodium hydride, which does not react with N2 under normal thermal conditions. Nitrogen plasma can produce reactive nitrogen species and also induce the dehydriding of NaH, which result in the activation and hydrogenation of N2 to surface NaNH2 species. The subsequent thermal‐hydrogenation of NaNH2 produces NH3 facilely. The stepwise chemical loop prevents ammonia from plasma‐induced cracking. This NaH‐mediated chemistry broadens the scope of hydrides as well as many other materials for N2 fixation, and also has prospect for other chemical transformations. [ABSTRACT FROM AUTHOR]

The synthesis of a series of new organophosphorane bis-ylide ligands is described. Upon their deprotonation, the stabilization of the ylide α-carbanion is achieved through the negative charge delocalization either over the π-system of the α-aryl groups bonded to carbanionic centers or over the {Cp}-type aromatic system in the case when the α-carbanion is involved in this system. The dibenzyl ylides [Ph2P(=CHAr)(CH2Ar)] were synthesized in situ starting from Ph2PLi and 2 equiv. of benzyl halides that significantly increased the yields of the target compounds. Ligands of the fluorenylidene, indenylidene, and cyclopentadienylidene types were synthesized in high yields. π-Stabilized organo-phosphorane ligands are readily metalated with potassium hydride and sodium amide to give the corresponding salts as solvates with THF. The reaction of 9-(diphenylphosphino)-fluorenide, Li[Ph2PC13H8], with Ph2PCl afforded the gem-bis(phosphine) ligand [9,9-(Ph2P)2C13H8] that readily gave the corresponding palladium complex [{κ-P, P-(Ph2P)2C13H8}PdCl2] in high yield. [ABSTRACT FROM AUTHOR]

An efficient and convenient palladium-catalyzed reductive system by employing sodium hydride as the hydrogen donor and acetic anhydride as an activator has been developed for transfer hydrogenation and acetylation of a wide range of N -heteroarenes including quinoline, phthalazine, quinoxaline, phenazine, phenanthridine, and indole. Moreover, acridine substrates could be directly reduced without the use of acetic anhydride. This protocol provides a simple method for the preparation of various saturated N -heterocycles. [ABSTRACT FROM AUTHOR]

A transition‐metal‐free intermolecular coupling reaction of halocompounds with styrenes in the presence of NaH and 1,10‐phenanthroline was developed. This reaction afforded hydrocarbonated products with complete anti‐Markovnikov selectivity. The method allows the use of a wide range of halocompounds, including aryl and alkyl halides, and good functional group tolerance. Detailed mechanistic studies indicated that an anilide anion generated in situ by the NaH‐mediated reduction of 1,10‐phenanthroline works as an electron donor and a hydrogen source. [ABSTRACT FROM AUTHOR]

A protocol for the generation of allylmagnesium reagents from 2‐aryl‐1,3‐dienes was developed using magnesium hydride (MgH2) that is generated in situ by solvothermal treatment of sodium hydride (NaH) and magnesium iodide (MgI2) in tetrahydrofuran (THF). Downstream functionalization of the resulting allylmagnesium reagents with carbonyl compounds or alkyl (pseudo)halides delivers branched products having an allylic quaternary carbon center, whereas that with chlorosilanes resulted in formation of linear allylsilanes in regio and stereoselective manners. Further derivatizations of the homoallylic alcohols and allylsilanes were also demonstrated. [ABSTRACT FROM AUTHOR]

New convenient synthetic methods in pyrazoline and pyrazolooxazine chemistry have been developed starting from 2,2‐dichlorovinylacetophenones 4, whose reaction with 2‐hydroxyethylhydrazine directly gave hitherto unknown 3‐aryl‐5‐dichloromethyl‐1‐(2‐hydroxiethyl)‐2‐pyrazolines 7 in high yields. These were found to be able to undergo cyclization to afford 2‐aryl‐6,7‐dihydro‐4H‐pyrazolo[5,1‐c][1,4]oxazines 10 upon treatment with sodium hydride. Compounds 10 could also easily be obtained in near quantitative yields by a one‐pot preparative process involving reaction of compounds 4 with 2‐hydroxyethylhydrazine followed by addition of sodium hydroxide. The simplicity and the high yield of this reaction make it much more attractive than the previously described multistep procedure. The molecular structure of 2‐(4‐chlorophenyl)‐6,7‐dihydro‐4H‐pyrazolo[5,1‐c][1,4]oxazine 10c was determined by x‐ray crystallography. [ABSTRACT FROM AUTHOR]

A simple method for design of some novel 1,2-benzoxaphosphinines 2–9, was achieved. The methodology depended on cyclization of 1-(2-hydroxy-phenyl)-3-phenylpropane-1,3-dione (1) as starting material with some phosphorus halides in dry solvent in the presence of a base. Reaction of the substrate 1 with some phosphorus halides, such as P,P-dichlorophenylphosphine, phenyl phosphonic dichloride, phenyl phosphorodichloridate, and phosphorus oxychloride in dry toluene containing triethylamine led to a predominant formation of 3-benzoyl-4-hydroxy-2H-1,2-benzoxaphosphinines 2–5, respectively. Under the same reaction conditions, the molecular structures of type 3-benzoyl-4H-1,2-benzoxaphosphinin-4-ones 6 and 7 were isolated by treatment of the substrate 1 with phosphorus pentachloride and phosphorus tribromide, respectively. In addition, the interesting 4-(1-phenyl-ethanoyl)-1,2,λ5-benzoxaphosphinines 8 and 9 were obtained by treatment of compound 1 with acetonyl and benzyl triphenylphosphonium chlorides, respectively, in dry dioxane and sodium hydride. The chemical structures of the title compounds were established by elemental analysis and spectral tools. [ABSTRACT FROM AUTHOR]

A series of new substituted chalcones with different positions of the isobornyl substituent in aromatic rings were synthesized in moderate and high yields by condensation of O-methoxy- and O-allyloxy derivatives of acetophenone with various benzaldehyde derivatives in the presence of sodium hydride in DMF. It was established that the presence of two allyloxy groups in the acylated derivatives of terpenophenols favors an increase in the yield of the substituted chalcone. A comparative evaluation of the antioxidant properties of the isobornylchalcones obtained was performed. It was shown that all compounds synthesized in this work exhibit pronounced antioxidant activity; however, particular characteristics depend strongly on the model system used. It was established that the presence, number, and positions of methoxy groups in the A- and B-rings are of importance for the implementation of the antioxidant activity of isobornylchalcones. [ABSTRACT FROM AUTHOR]

The sequence of reactions of the phosphorus‐containing aryllithium compound 5‐t‐Bu‐1,3‐[(P(O)(O‐i‐Pr)2]2C6H2Li (ArLi) with Ph2PCl, KMnO4, elemental sulfur and elemental selenium, respectively, gave the aryldiphenylphosphane chalcogenides 5‐t‐Bu‐1,3‐[(P(O)(O‐i‐Pr)2]2C6H2P(E)Ph2 (1, E=O; 2, E=S; 3, E=Se). Compound 1 partially hydrolysed giving [5‐t‐Bu‐1‐{(P(O)(O‐i‐Pr)2}‐3‐{(P(O)(OH)2}C6H2]P(O)Ph2 (4). The reaction of ArLi with PhPCl2 provided the benzoxaphosphaphosphole [1(P), 3(P)‐P(O)(O‐i‐Pr)OPPh‐6‐t‐Bu‐4‐P(O)(O‐i‐Pr)2]C6H2P (5i) as a mixture of the two diastereomers. The oxidation of 5i with elemental sulfur gave the benzoxaphosphaphosphole sulfide [1(P), 3(P)‐P(O)(O‐i‐Pr)OP(S)Ph‐6‐t‐Bu‐4‐P(O)(O‐i‐Pr)2]C6H2 (5) as pair of enantiomers P1(R), P3(S)/P1(S), P3(R) of the diastereomer (RS/SR)‐5 (5b). The aryldiphenylphosphane 5‐t‐Bu‐1,3‐[(P(O)(O‐i‐Pr)2]2C6H2PPh2 (6) was obtained from the reaction of the corresponding aryldiphenylphosphane sulfide 2 with either sodium hydride, NaH, or disodium iron tetracarbonyl, Na2Fe(CO)4. The oxidation of the aryldiphenylphosphane 6 with elemental iodine and subsequent hydrolysis yielded the aryldiphenyldioxaphosphorane 9‐t‐Bu‐2,6‐(OH)‐4,4‐Ph2‐3,5‐O2‐2,6‐P2‐4λ5‐P‐[5.3.1.0]‐undeca‐1(10),7(11),8‐triene (7). Both of its diastereomers, (RR/SS)‐7 (7a) and (RS/SR)‐7 (7b), were separated as their chloroform and i‐propanol solvates, 7a⋅2CHCl3 and 7b⋅i‐PrOH, respectively. DFT calculations accompanied the experimental work. [ABSTRACT FROM AUTHOR]

Metal hydrides such as MgH2 and NaBH4 are among the materials for with the highest potential solid-state hydrogen storage. However, unlike gas and liquid storage, a dehydrogenation process has to be done prior to hydrogen utilization. In this context, the hydrolysis method is one of the possible methods to extract or generate hydrogen from the materials. However, problems like the MgH2 passivation layer, high cost and sluggish self-hydrolysis of NaBH4 are the known limiting factors for this process, but they can be overcome with the help of catalysts. In this works, selected studies have been reviewed on the performance of catalysts like chloride, oxide, fluoride, platinum, ruthenium, cobalt and nickel-based on the MgH2 and NaBH4 system. These studies show a significant enhancement in the amount of hydrogen released as compared to the hydrolysis of the pure MgH2 and NaBH4. Therefore, the addition of catalysts is proven as one of the options in improving hydrogen generation via the hydrolysis of MgH2 and NaBH4. [ABSTRACT FROM AUTHOR]

A new compound NaCd4Sb3 (R3‾m, a=4.7013(1) Å, c=35.325(1), Å, Z=3, T=100 K) featuring the RbCd4As3 structure type has been discovered in the Na−Cd−Sb system, in addition to the previously reported NaCdSb phase. NaCd4Sb3 and NaCdSb were herein synthesized using sodium hydride as the source of sodium. The hydride method allows for targeted sample composition, improved precursor mixing, and an overall quicker synthesis time when compared to traditional methods using Na metal as a precursor. The NaCd4Sb3 structure was determined from single‐crystal X‐ray diffraction and contained the splitting of a Cd site not seen in previous isostructural phases. NaCd4Sb3 decomposes into NaCdSb plus melt at 766 K, as determined via in‐situ high‐temperature PXRD. The electronic structure calculations predict the NaCd4Sb3 phase to be semi‐metallic, which compliments the measured thermoelectric property data, indicative of a p‐type semi‐metallic material. The crystal structure, elemental analysis, thermal properties, and electronic structure are herein discussed in further detail. [ABSTRACT FROM AUTHOR]

The hunt for a cleaner energy carrier leads us to consider a source that produces no toxic byproducts. One of the targeted alternatives in this approach is hydrogen energy, which, unfortunately, suffers from a lack of efficient storage media. Solid-state hydrogen absorption systems, such as lithium amide (LiNH2) systems, may store up to 6.5 weight percent hydrogen. However, the temperature of hydrogenation and dehydrogenation is too high for practical use. Various molar ratios of LiNH2 with sodium hydride (NaH) and potassium hydride (KH) have been explored in this paper. The temperature of hydrogenation for LiNH2 combined with KH and NaH was found to be substantially lower than the temperature of individual LiNH2. This lower temperature operation of both LiNH2-NaH and LiNH2-KH systems was investigated in depth, and the eutectic melting phenomenon was observed. Systematic thermal studies of this amide-hydride system in different compositions were carried out, which enabled the plotting of a pseudo-binary phase diagram. The occurrence of eutectic interaction increased atomic mobility, which resulted in the kinetic modification followed by an increase in the reactivity of two materials. For these eutectic compositions, i.e., 0.15LiNH2-0.85NaH and 0.25LiNH2-0.75KH, the lowest melting temperature was found to be 307 °C and 235 °C, respectively. Morphological studies were used to investigate and present the detailed mechanism linked with this phenomenon. [ABSTRACT FROM AUTHOR]

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The indazole scaffold represents a promising pharmacophore, commonly incorporated in a variety of therapeutic drugs. Although indazole-containing drugs are frequently marketed as the corresponding N-alkyl 1H- or 2H-indazole derivative, the efficient synthesis and isolation of the desired N-1 or N-2 alkylindazole regioisomer can often be challenging and adversely affect product yield. Thus, as part of a broader study focusing on the synthesis of bioactive indazole derivatives, we aimed to develop a regioselective protocol for the synthesis of N-1 alkylindazoles. Initial screening of various conditions revealed that the combination of sodium hydride (NaH) in tetrahydrofuran (THF) (in the presence of an alkyl bromide), represented a promising system for N-1 selective indazole alkylation. For example, among fourteen C-3 substituted indazoles examined, we observed > 99% N-1 regioselectivity for 3-carboxymethyl, 3-tert-butyl, 3-COMe, and 3-carboxamide indazoles. Further extension of this optimized (NaH in THF) protocol to various C-3, -4, -5, -6, and -7 substituted indazoles has highlighted the impact of steric and electronic effects on N-1/N-2 regioisomeric distribution. For example, employing C-7 NO2 or CO2Me substituted indazoles conferred excellent N-2 regioselectivity (≥ 96%). Importantly, we show that this optimized N-alkylation procedure tolerates a wide structural variety of alkylating reagents, including primary alkyl halide and secondary alkyl tosylate electrophiles, while maintaining a high degree of N-1 regioselectivity.

A new cascade aromatic nucleophilic substitution-O[1,3] sigmatropic shift-Smiles rearrangement-amide and ester exchange reaction of 2/4-nitroaryl halides and N-acyl-N-arylhydroxylamines was observed and investigated in the presence of sodium hydride in THF, affording 2-((2/4-nitroaryl)amino)aryl carboxylate derivatives in low to excellent yields depending upon the electrophilicity of 2/4-nitroaryl halides. Generally, aryl halides with strong electron-withdrawing 2,4,6-trisubstituents gave the rearranged products in satisfactory to excellent yields. The current reaction provides not only an unprecedented cascade fourstep reaction, but also a new strategy for the synthesis of 2-hydroxydiarylamine derivatives under transition metal-free conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] • Triterpenoic acids benzylamides were synthesized and sulfamoylated. • These compounds were tested as inhibitors of carbonic anhydrases (CA) I, II, VA and IX. • An Asiatic acid derived trisulfamate held strong inhibitory effects for CA VA. • This compound showed a K i = 36.2 nM thus outperforming standard acetalzolamide. This investigation delves into the inhibitory capabilities of a specific set of triterpenoic acids on diverse isoforms of human carbonic anhydrase (h CA). Oleanolic acid (1), maslinic acid (2), betulinic acid (3), platanic acid (4), and asiatic acid (5) were chosen as representative triterpenoids for evaluation. The synthesis involved acetylation of parent triterpenoic acids 1 – 5 , followed by sequential reactions with oxalyl chloride and benzylamine, de-acetylation of the amides, and subsequent treatment with sodium hydride and sulfamoyl chloride, leading to the formation of final compounds 21 – 25. Inhibition assays against h CAs I, II, VA, and IX demonstrated noteworthy outcomes. A derivative of betulinic acid, compound 23 , exhibited a K i value of 88.1 nM for h CA VA, and a derivative of asiatic acid, compound 25 , displayed an even lower K i value of 36.2 nM for the same isoform. Notably, the latter compound displayed enhanced inhibitory activity against h CA VA when compared to the benchmark compound acetazolamide (AAZ), which had a K i value of 63.0 nM. Thus, this compound surpasses the inhibitory potency and isoform selectivity of the standard compound acetazolamide (AAZ). In conclusion, the research offers insights into the inhibitory potential of selected triterpenoic acids across diverse h CA isoforms, emphasizing the pivotal role of structural attributes in determining isoform-specific inhibitory activity. The identification of compound 25 as a robust and selective h CA VA inhibitor prompts further exploration of its therapeutic applications. [ABSTRACT FROM AUTHOR]

Sodium silicide Na4Si4 is a reductive and reactive source of silicon highly relevant to designing non-oxidic silicon materials, including clathrates, various silicon allotropes, and metal silicides. Despite the importance of this compound, its production in high amounts and high purity is still a bottleneck with reported methods. In this work, we demonstrate that readily available silicon nanoparticles react with sodium hydride with a stoichiometry close to the theoretical one and at a temperature of 395 °C for shorter duration than previously reported. This enhanced reactivity of silicon nanoparticles makes the procedure robust and less dependent on experimental parameters, such as gas flow. As a result, we deliver a procedure to achieve Na4Si4 with purity of ca. 98 mol% at the gram scale. We show that this compound is an efficient precursor to deliver selectively type I and type II sodium silicon clathrates depending on the conditions of thermal decomposition. [ABSTRACT FROM AUTHOR]

Sodium silicide Na4Si4 is a reductive and reactive source of silicon highly relevant to designing non-oxidic silicon materials, including clathrates, various silicon allotropes, and metal silicides. Despite the importance of this compound, its production in high amounts and high purity is still a bottleneck with reported methods. In this work, we demonstrate that readily available silicon nanoparticles react with sodium hydride with a stoichiometry close to the theoretical one and at a temperature of 395 °C for shorter duration than previously reported. This enhanced reactivity of silicon nanoparticles makes the procedure robust and less dependent on experimental parameters, such as gas flow. As a result, we deliver a procedure to achieve Na4Si4 with purity of ca. 98 mol% at the gram scale. We show that this compound is an efficient precursor to deliver selectively type I and type II sodium silicon clathrates depending on the conditions of thermal decomposition. [ABSTRACT FROM AUTHOR]

An unexpected formation of carbamothioates by a sodium hydride-mediated reaction of arylmethyl isocyanides with xanthate esters in DMF is reported. The products thus obtained were compared with the carbamothioates obtained by the sodium hydride-mediated condensation of the corresponding benzylamines and xanthate esters in DMF. To account for these unexpected reactions, a mechanism is proposed in which the key steps are supported by quantum chemical calculations.

In the present paper, the blast furnace slag (BFS) supported Co-B catalyst were investigated in detail. The impregnation-chemical reduction method was used while hydrochloric (HCl) acid treated BFS samples (BFS+) were prepared. Catalyst samples were analyzed in three main groups as base BFS (BFS0), BFS0-Co-B and BFS+-Co-B. The effects of these catalyst samples on hydrogen production from the solid-state sodium boron hydride (NaBH 4) are analyzed in this study. The effects of some parameters such as the ingredients of blast furnace slag, the molarity of hydrochloric acid treatment, the Co percentages and the solution temperatures were investigated on the hydrolysis performance of NaBH 4. The NaBH 4 hydrolysis reaction with the BFS0 is treated by the BFS+-Co-B-20% catalyst was completed approximately 25 min and the hydrolysis reaction with the BFS0-Co-B-20% catalyst was completed approximately 20 min whereas the hydrolysis reaction of NaBH 4 was completed in 1 h 35 min. The hydrogen production rates at pre-heated to max 40, 50 and 60 °C were measured as 55.12, 64.47 and 70.41 L/min.g catalyst , respectively. According to another result of the study, the high-efficiency solid-state BFS-Co-B & NaBH 4 mixtures were covered with the PVA (Polyvinyl alcohol) film to make them more resistant to environmental effects such as humidity. • BFS was used as a catalyst for the first time within the NaBH 4 hydrolysis process. • 20% Co-B-BFS acid untreated sample improved total hydrogen production 34.7%. • 50% Co-B-BFS acid treated sample improved total hydrogen production 25.1%. • Best result in terms of "L/min.gcatalyst" was obtained by acid treated 40% Co-B-BFS. • PVA technique used to protect NaBH4 from environmental effects. [ABSTRACT FROM AUTHOR]

2‐Amino‐3‐(het)aryl‐quinoxalines were synthesized by the cyclization reaction between 2‐oxo‐ethanimidothioates and o‐phenylenediamine in the presence of acid catalyst p‐TSA in toluene at 80 °C. The products were obtained in 58–84 % yields. The required substrates 2‐oxo‐ethanimidothioates were synthesized by the condensation reaction between α‐oxodithioester and amine in the presence of sodium hydride in DMF followed treatment with methyl iodide. [ABSTRACT FROM AUTHOR]

[Display omitted] Highly chemoselective transfer hydrogenation of the C C bonds of α-keto substituted acrylate compounds catalyzed by an [IrCl 2 Cp*] 2 -TsEN Complex (Cp* = η5-C 5 Me 5) in water using sodium formate as hydride source has been developed. A variety of α-keto substituted acrylate compounds were reduced smoothly under 0.5 mol% of Iridium catalyst with 1.0 mol% ligand TsEN and 3 equiv. of sodium formate providing the desired product α-alkyl-β-keto esters in high to excellent yields (80–99 %). The procedure presented is simple and makes this method suitable for practical use. [ABSTRACT FROM AUTHOR]

Introduction: Phenothiazines are classes of heterocyclic compounds with wide spectrum of biological properties especially in the mental disorders. Recent reports have shown promising anticancer, antiplasmid, antibacterial, anti-inflammatory and immunosuppressive activities of both classical and new derivatives of phenothiazines. Previously synthesized library of dipyridothiazines have demonstrated interesting antiproliferative, anticancer, antioxidant and immunosuppressive activities. The current project aims to obtain new derivatives of dipyridothiazines, which are expected to possess promising anticancer activity. Methods: New twelve dimer of dipyridothiazines were synthesized effective reactions of involving dipyridothiazines with selected linkers, in the presence of sodium hydride, and dimethylformamide (DMF). The structures of the new compounds were determine using NMR and 2D NMR spectroscopy (COSY, ROESY, HSQC, HMBC) as well as mass spectrometry (HR MS). All compounds were then subjected to biologically evaluation for their anticancer activity against colon (SW480) and breast cancer cell lines (MCF7). Results: Promising results were obtained, which encourage further research to explore the mechanism of anticancer activity and cytotoxicity. Conclusion: The research study underscores the potential importance of new dimers from dipirydothiazines in the search for targeted anti-cancer agents. [ABSTRACT FROM AUTHOR]

Novel class of amino pyrimidine thioglycoside derivatives were designed from sodium 2-cyano-3-(arylamino)prop-1-ene-1,1-bis(thiolate) 1a-d and guanidine hydrochloride 2 to afford the corresponding sodium 2,6-diamino-5-aryl-1,2-dihydropyrimidine-4-thiolate 3a-d, which in coupling with peracylated α-D-gluco- and galactopyranosyl bromides 5a,b in DMF gave the corresponding pyrimidine thioglycosides 6a-h. Acidification of 2,6-diamino-5-aryl-1,2-dihydropyrimidine-4-thiolate salts 3a-d with hydrochloric acid formed the corresponding pyrimidine-4-thioles 4a-d. The latter were stirred with peracetylated halo sugars α-D-gluco- and galacto-pyranosyl bromides in sodium hydride and DMF to yield the pyrimidine thioglycosides 6a-h. Deacetylation of the pyrimidine thioglycosides gave the corresponding free pyrimidine thioglycosides 7a-h. The compounds were characterized by 13C NMR, 1H NMR, and IR. The pyrimidine thioglycosides 6a-h and free pyrimidine thioglycosides 7a-h were tested against H5N1 virus strain and exhibited high to moderate activity. [ABSTRACT FROM AUTHOR]

The title compound (E)-1,3-dimethyl-2-[3-(4-nitrophenyl)triaz-2-enylidene]-2,3-dihydro-1H-imidazole, C11H12N6O2, has monoclinic (C2/c) symmetry at 100 K. This triazene derivative was synthesized by the coupling reaction of 1,3-dimethylimidazolium iodide with 1-azido-4-nitro benzene in the presence of sodium hydride (60% in mineral oil) and characterized by ¹H NMR, 13C NMR, IR, mass spectrometry, and single-crystal X-ray diffraction. The molecule consists of six-membered and five-membered rings, which are connected by a triazene moiety (-N=N-N-). In the solid-state, the molecule is found to be planar due to conjugation throughout the molecule. The extended structure shows two layers of molecules, which present weak intermolecular interactions that facilitate the stacked arrangement of the molecules forming the extended structure. Furthermore, there are several weak pseudo-cyclical interactions between the nitro oxygen atoms and symmetry-adjacent H atoms, which help to arrange the molecules. [ABSTRACT FROM AUTHOR]

Carbimidothioates are synthesized by the reaction of Grignard reagents or heteroaryl lithium compounds with arylisothiocyanates followed by treatment with methyl iodide. Further, application of these intermediates in the synthesis of β‐enaminones by their condensation with methyl ketones in the presence of sodium hydride in DMF is reported. This method offers a new gateway for the synthesis of β‐enaminones, which are important building blocks in synthetic organic chemistry. [ABSTRACT FROM AUTHOR]

A protocol for regio‐controlled hydromagnesiation of 1,3‐enynes was developed using magnesium hydride that is generated in situ by solvothermal treatment of sodium hydride (NaH) and magnesium iodide (MgI2) in THF. The resulting allenylmagnesium species could be converted into tri‐ and tetra‐substituted allenes by subsequent treatment with various carbon‐ and silicon‐based electrophiles with the aid of CuCN as a catalyst. [ABSTRACT FROM AUTHOR]

Stereoselective catalytic synthesis of 3‐trifluoromethyl indolines through the [4+1] cycloaddition of benzoxazinones and sulfur ylides in a transition‐metal‐free manner was developed. In the presence of a catalytic amount of sodium hydride, aza‐ortho‐quinone methide intermediates were formed from trifluoromethyl benzoxazinones through decarboxylation after the first nucleophilic attack of sulfur ylides, which progressed to a second nucleophilic attack of sulfur ylides, resulting in the [4+1] cycloaddition. The key for this catalytic transformation is the dual attack of sulfur ylides on substrates. This unique transition‐metal‐free protocol is applicable to the synthesis of non‐fluorinated vinyl‐, ethynyl‐ or methyl‐substituted indolines. The synthesis of 3‐trifluoromethyl indoles was also achieved described under stoichiometric conditions. [ABSTRACT FROM AUTHOR]

New 1,5-diaryl-3-(pyridin-4′-yl)pentane-1,5-diones were synthesized via the tandem reaction of pyridin-4-carbaldehyde with methyl (aryl) ketones in the presence of sodium hydride. The treatment of the diketones with ammonium acetate resulted in heterocyclization to 2,6-diaryl-4-(pyridin-4′-yl)pyridines. [ABSTRACT FROM AUTHOR]

The study focuses on hydrogen desorption characteristics of lithium hydride (LiH), sodium hydride (NaH), calcium hydride (CaH 2), and titanium hydride (TiH 2) which permits a possible path regarding challenging goals of US DOE standards. This research reported the consequences of enrichment in hydrogen uptake 7.02 wt% in lithium hydride, 7.71 wt% in sodium hydride, 5.91 wt% in calcium hydride, and 5.00 wt% in titanium hydride using silicon as an additive when evaluated with the help of volumetric technique. The ball milling process with silicon additive for LiH, NaH, CaH 2 , and TiH 2 shows depletion in dehydrogenation temperatures 523 K, 453 K, 488 K, and 463 K respectively. Similarly, the reduction in the activation energies reported due to ball milling process with silicon additive are 37 kJ/mol for lithium hydride, 42 kJ/mol for sodium hydride, 56 kJ/mol for calcium hydride and 45 kJ/mol for titanium hydride compared with crystalline powder samples of the respective materials. The outcome of Fourier-transform infrared spectroscopy of milled hydride samples after decomposition intimate rapid decrease in transmittance intensities due to hydrogen release because of the destabilization effect caused by silicon additive. The porosity and sponginess in high-resolution Transmission electron microscopy images after dehydrogenation reveals the hydrogen desorption from the sample materials. • TG-DTA for isothermal decomposition of LiH, NaH, CaH 2 & TiH 2 with 10% Si additive. • Reduction in dehydrogenation temperature & activation energy values by Si additive. • Characterization of samples by FTIR & TEM spectroscopy methods for validation. [ABSTRACT FROM AUTHOR]

Mild mono‐ and di‐hydrodehalogenative reductions of gem‐dibromocyclopropanes are described, providing an easy and green approach towards the synthesis of cyclopropanes. The methodology utilizes 0.5–5 mol % TMPhen‐nickel as the catalyst, which, when activated with a hydride source such as sodium borohydride, cleanly and selectively dehalogenates dibromocyclopropanes. Double reduction proceeds in a single operation at temperatures between 20–45 °C and at atmospheric pressure in an aqueous designer surfactant medium. At lower loading and either in the absence of ligand or in the presence of 2,2′‐bipyridine, this new technology can also be used to gain access to not only monobrominated cyclopropanes, interesting building blocks for further use in synthesis, but also mono‐ or di‐deuterated analogues. Taken together, this base‐metal‐catalyzed process provides access to cyclopropyl‐containing products and is achieved under environmentally responsible conditions. [ABSTRACT FROM AUTHOR]

A new method for the synthesis of α‐branched amines by reductive functionalization of tertiary carboxamides and lactams is described. The process relies on the efficient and controlled reduction of tertiary amides by a sodium hydride/sodium iodide composite, in situ treatment of the resulting anionic hemiaminal with trimethylsilyl chloride and subsequent coupling with nucleophilic reagents including Grignard reagents and tetrabutylammonium cyanide. The new method exhibits broad functional‐group compatibility, operates under transition‐metal‐free reaction conditions, and is suitable for various synthetic applications on both sub‐millimole and on multigram scales. [ABSTRACT FROM AUTHOR]

An efficient gold‐catalyzed intramolecular regioselective synthesis of pyrazolo[1,4]oxazepines were developed from alkynyl‐substituted pyrazoles via 7‐endo dig cyclization. In this reaction a new C–N bond was formed and substituted pyrazolo[1,4]oxazepines were obtained in moderate to very good yields. Whereas alkynyl‐substituted pyrazoles treated with sodium hydride produced the corresponding pyrazolo[1,4]oxazines regioselectively, via 6‐exo dig cyclization in one‐pot synthesis. [ABSTRACT FROM AUTHOR]

An in situ generated zinc ascorbate pre-catalyst for cyclic carbonate (CC) synthesis via CO2 coupling with epoxides under ambient conditions was reported. Spectroscopic measurements indicated that CO2 was inserted into the zinc ascorbate complex through the formation of an activated zinc carbonate catalyst upon abstracting the enediol protons with sodium hydride. The aliphatic diols were not activated under the applied conditions and did not interfere with either the process of cycloaddition or CO2 activation. The catalyst was active against different terminal epoxides, with a conversion of 75 and 85%, when propylene oxide and styrene oxide were used at 20 and 50 °C, respectively under 1 atm CO2 for 17 h, which was considered a good advancement for heterogeneous based catalysis. Moreover, green chemistry principles were applied to ultimately end up with more ecofriendly approaches for the synthesis of CC following a simple balloon technique. Herein, we used zinc as a sustainable metal, together with ascorbic acid as a bio-renewable material in addition to CO2 as a renewable feed-stock. Furthermore, waste prevention was achieved using the reaction side product, viz., NaBr as a co-catalyst. [ABSTRACT FROM AUTHOR]

Cyclopropylacetylene and N,N,N′,N′,N′′,N′′-hexamethylguanidinium chloride (1a) react to give the orthoamide derivative 8c, in the presence of sodium hydride. 8c is transformed by elemental iodine to the vinylogous guanidinium salt 6f. Anion metathesis with the salts 5a, 5e, 6g delivers vinylogous guanidinium salts 5e–5i, 12a with counter ions derived from carbon acids (tricyanomethane, 1,1,3,3-tetracyano-propene). Phenylogous amidinium salts 15 guanidinium salts 19, 21 and the phenylogous orthoamide derivatives of formic acid 18 and carbonic acid 33 have been prepared. [ABSTRACT FROM AUTHOR]