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The systematic study of the reaction of M[PF6] salts and Me3SiCN led to a synthetic method for the synthesis and isolation of a series of salts containing the unprecedented [PF2(CN)4]− ion in good yields. The reaction temperature, pressure, and stoichiometry were optimized. The crystal structures of M[PF2(CN)4] (M=[nBu4N]+, Ag+, K+, Li+, H5O2+) were determined. X-ray crystallography showed the exclusive formation of the cis isomer in accord with 31P and 19F solution NMR spectroscopy data. Starting with the K[PF2(CN)4] the room temperature ionic liquid EMIm[PF2(CN)4] was prepared exhibiting a rather low viscosity. [ABSTRACT FROM AUTHOR]

Always look on the bright azide of life: The synthesis of Millon's base azido salt [Hg2N]N3, and the metastable β‐Hg(N3)2, along with their full characterization is possible for the first time and closes an open gap in azide chemistry. [ABSTRACT FROM AUTHOR]

Palladium(0)-catalyzed Suzuki and Sonogashira crosscoupling reactions of the bis(triflates) of 2,4- and 3,4-dihydroxybenzophenone afforded 2,4- and 3,4-diarylbenzophenones, respectively. The reactions proceeded with very good site-selectivity in favor of position 4. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of salts bearing highly labile pseudohalogen-substituted aminophosphenium cations of the type [(Me3Si)2NPX][GaCl4] (X = NCO, NCS, 0(SiMe3)) and their respective reactivity toward Lewis bases (4-dimethylaminopyridine, dmap) and dienes (2,3-dimethyl-l,3-butadiene, dmb; 1,3-cyclo-hexadiene, chd) are described. As π-acidic species, aminophosphenium cations react with dmap at low temperatures to yield adduct salts of the type [(Me3Si)2NP(dmap)X][GaCl4] (X = CI, N3 NCO) which were fully characterized. In the reaction with dienes at --50 °C, salts bearing phospholenium cations were obtained that could be structurally characterized. The crystal structures of novel 7-phosphanorbornenium cations of the type [(Me3Si)2NP(C6H8)X] [GaClJ (X = CI, N3, NCO) are reported. All compounds were further investigated by means of density functional theory, and the bonding situation was accessed by Natural Bond Orbital (NBO) analysis. [ABSTRACT FROM AUTHOR]

Abstract: 6H-benzo[c]chromen-6-ones were prepared by base mediated cyclocondensation of 1,3-dicarbonyl compounds with 4-chloro-3-formylcoumarin. [Copyright &y& Elsevier]

Abstract: Fluoranthenes were prepared by domino two-fold Heck/electrocyclization/dehydrogenation reactions of 1,2-dibromoacenaphthylene. [Copyright &y& Elsevier]

Abstract: 6-Aryl-2,3-dihydro-4H-pyran-4-ones were prepared in one step by cyclocondensation of 1,3-diketone dianions with aldehydes. The use of hydrochloric acid (10%) for the aqueous work-up proved to be very important. [Copyright &y& Elsevier]

• Synthesis of nicotinaldehyde-based crystals is done through Suzuki-Miyaura coupling reaction. • Structures were analyzed through different spectroscopic techniques. • The experimental results show good agreement with theoretical results. • NLO and electronic properties were also studied. The analogues of pyridine ring structures demonstrate various physiological as well as biological activities. The current research is based on experimental along with computational investigations of two new phenyl substituted nicotinaldehyde derivatives; 2-(2,4-difluorophenyl)pyridine-3-carbaldehyde (DFPPC) and 2-(2,5-dichlorophenyl)pyridine-3-carbaldehyde (DCPPC). For structural optimization of DFPPC as well as DCPPC and to explore nonlinear optical properties, computational quantum chemical analysis was executed via density functional theory (DFT) calculations by employing M06 level with 6–311G(d,p) basis set. A consensus among theoretical (DFT) and experimental (SC-XRD) results was observed by the calculation of geometric parameters. Molecular electrostatic potential (MEP), natural bond orbital (NBO) analysis, natural population analysis (NPA), nonlinear optical (NLO), global reactivity parameters (GRPs), and frontier molecular orbital (FMO) exploration were carried out at M06/6–311G(d,p), to comprehend hyper-conjugative interactions, electron density, electronic communications and oscillation strength. The HOMO/LUMO energy gap of DCPPC (5.108 eV) was observed to be lower than DFPPC i.e., 5.170 eV, which resulted in its higher value of global softness (0.196 E h) along with lower global hardness (2.554 E h) value than DFPPC. The NLO attributes of DFPPC as well as DCPPC was calculated by evaluating the total dipole moment (μ tot), average linear polarizability ⟨ α ⟩ and second hyperpolarizability (γ tot) at aforementioned level. From the NLO results, it was observed that DCPPC exhibits a higher average linear polarizability value such as 3.0772 × 10−23 esu than DFPPC i.e., 2.6116 × 10−23 esu. Whereas, higher results of γ tot were observed for DFPPC i.e., 3.2455 × 10−35 than DCPPC (3.0708 × 10−35 esu). The distinguished NLO characteristics revealed that, both the chromophores (DFPPC and DCPPC) can be recognized as highly efficient NLO materials for future applications. [ABSTRACT FROM AUTHOR]

The systematic study of the reaction of M[PF6] salts and Me3SiCN led to a synthetic method for the synthesis and isolation of a series of salts containing the unprecedented [PF2(CN)4]− ion in good yields. The reaction temperature, pressure, and stoichiometry were optimized. The crystal structures of M[PF2(CN)4] (M=[nBu4N]+, Ag+, K+, Li+, H5O2+) were determined. X-ray crystallography showed the exclusive formation of the cis isomer in accord with 31P and 19F solution NMR spectroscopy data. Starting with the K[PF2(CN)4] the room temperature ionic liquid EMIm[PF2(CN)4] was prepared exhibiting a rather low viscosity. [ABSTRACT FROM AUTHOR]

Abstract: An efficient palladium-catalyzed cyclization of o-chlorohetaryl ynones with aliphatic and aromatic primary amines represents a simple access to a wide range of benzo[b][1,8]naphthyridin-4(1H)-one and pyrido[2,3-b]quinoxalin-4(1H)-one derivatives in good to excellent yields. [Copyright &y& Elsevier]

Abstract: The TiCl4-mediated [3+3] cyclocondensation of 1,3-bis(silyloxy)-1,3-butadienes with 1-chloro-1,1-difluoro-4,4-dimethoxybut-3-en-2-one or 1,1-difluoro-4,4-dimethoxybut-3-en-2-one afforded CF2Cl- and CF2H-substituted salicylates, respectively. The Me3SiOTf-mediated [3+3] cyclocondensation of the same building blocks provided CF2Cl- and CF2H-substituted pyran-4-ones and CF2Cl-substituted cyclohexenones. The formation of CF2H-substituted cyclohexenones was not observed. Besides the type of Lewis acid, the product distribution is also influenced by the substitution pattern of the 1,3-bis(silyloxy)-1,3-butadiene: The Me3SiOTf mediated cyclization of C4-unsubstituted dienes resulted in the formation of CF2Cl-substituted pyran-4-ones, while the cyclization of C4-substituted dienes afforded CF2Cl-substituted cyclohexenones. The TiCl4-mediated cyclization of C4-substituted dienes with 1,1-difluoro-4,4-dimethoxybut-3-en-2-one failed. Therefore, 3-substituted CF2H-salicylates were prepared by transformation of the respective CF2Cl-salicylates with tributyltin hydride. [Copyright &y& Elsevier]

(Benzyloxycarbonyl)-protected 3,4-benzo-7-hydroxy-2,9-diazabicyclo[3.3.1]non-7-enes were prepared by one-pot cyclizations of 1,3-bis(silyl enol ethers) with quinazolines. Subsequent hydrogenation resulted in one-pot deprotection and rearrangement to give 2-(2-aminophenyl)-2,3-dihydropyridin-4(1 H)-ones. [ABSTRACT FROM AUTHOR]

Abstract: 4-Chloro-3-(trifluoroacetyl)- and 4-chloro-3-(methoxalyl)coumarins react with electron-rich aminoheterocycles, dimethyl 1,3-acetonedicarboxylate, hydrazines, alkyl thioglycolates, and methyl sarcosinate to give a variety of 3,4-heteroannulated coumarins. The starting materials were prepared by the reaction of 4-hydroxycoumarin with trifluoroacetic anhydride and methyl 2-chloro-2-oxoacetate in the presence of trimethylsilylchloride. An NMR study and X-ray crystallographic analysis are reported. [Copyright &y& Elsevier]

Abstract: Difluoromethyl-containing heteroannulated pyridines, pyrimidines and pyrazoles are prepared by a two step method. The regioselective cyclizations of electron-excessive aminoheterocycles, hydrazines and amidines with CF2Cl-substituted 1,3-dicarbonyl compounds provide the corresponding CF2Cl-substituted heterocycles. Subsequent radical reactions with trimethylstannane or allyltrimethylstannane gave difluoromethyl-containing heteroannulated pyridines, pyrimidines and pyrazoles, respectively. [Copyright &y& Elsevier]

Abstract: Di-, tri- and tetra-alkenylindoles were prepared by palladium(0)-catalyzed Heck cross-coupling reactions of di-, tri- and tetrabromo-N-methylindoles. The reactions were carried out at 90 °C using a novel biaryl monophosphine ligand developed by Buchwald and co-workers. 1,2-Dihydrocarbazoles were formed by a domino ‘twofold Heck/6π-electrocyclization’ when the reaction was carried out at higher temperature. The regioselectivity of the Heck reaction of 2,3,6-tribromo-N-methylindoles was in favour of carbon atoms C-2 and C-3. The 1,2-dihydrocarbazoles were transformed, by Pd/C-catalyzed dehydrogenation, into the corresponding carbazoles in high yield. [Copyright &y& Elsevier]

Abstract: Suzuki–Miyaura reactions of N-protected tribromopyrazoles were studied. The reactions proceed with excellent site-selectivity. The first attack occurs at position 5, while the second and third attack occur at positions 3 and 4, respectively. A variety of 3,4,5-triaryl-pyrazoles, 3,5-diaryl-4-bromopyrazoles, and 5-aryl-3,4-dibromopyrazoles were efficiently prepared. The products are not readily available by other methods. [Copyright &y& Elsevier]

Abstract: A formal [3+3] cyclocondensation of 1,3-bis(silyl enol ethers) with the little-known 4,4-dimethylthio-1,1,1-trifluorobut-3-en-2-one was studied. In contrast to 4,4-dimethoxy-1,1,1-trifluorobut-3-en-2-one, this α-oxoketene dithioacetal reacts with 1,3-bis(trimethylsilyloxy)-1,3-butadienes in the presence of TiCl4 to give mainly 6-methylthio-4-(trifluoromethyl)salicylates via 1,2-addition. The scope and limitations of the reaction are discussed. [Copyright &y& Elsevier]

Abstract: The reaction of the dianion of 1,1,1-trifluoro-pentane-2,4-dione with aldehydes and subsequent addition of hydrochloric acid afforded 2,3-dihydro-6-trifluoromethyl-pyran-4-ones. The reaction of the dianion of acetylacetone with fluorinated benzaldehydes gave the corresponding fluorinated 2-aryl-2,3-dihydro-6-methyl-pyran-4-ones. All reactions proceeded in very good yield and with very good regioselectivity. [ABSTRACT FROM AUTHOR]

Abstract: The palladium(0)-catalyzed Suzuki cross-coupling reaction of the bis(triflates) of phenyl 1,4-dihydroxy-2-naphthoate afforded various 1,4-diaryl-2-naphthoates. The reactions proceeded with very good site-selectivity. Due to electronic reasons, the first attack occurred at the sterically more hindered position C-1. [Copyright &y& Elsevier]

Abstract: The [3+3] cyclization of 1,3-bis(silyloxy)-1,3-butadienes with 1-hydroxy-5-silyloxy-hex-4-en-3-ones resulted in the one-pot formation of 3-aryl-3,4-dihydroisocoumarins. The reactions proceeded by regioselective cyclization to give 6-(2-aryl-2-chloroethyl)salicylates, which underwent a silica gel-mediated lactonization. The cyclizations of protected 1-amino-5-silyloxy-hex-4-en-3-ones proved to be not regioselective. [Copyright &y& Elsevier]

Abstract: Functionalized triarylmethanes are prepared in two steps by FeCl3-catalyzed benzylation of acetylacetone to give 3-(diarylmethyl)pentane-2,4-diones and subsequent formal [3+3] cyclization of the latter with 1,3-bis(trimethylsilyloxy)-1,3-dienes. [Copyright &y& Elsevier]

Abstract: The [4+2] cycloaddition of 1-ethoxy-2-chloro-1,3-bis(trimethylsilyloxy)-1,3-diene with dimethyl acetylenedicarboxylate (DMAD) afforded dimethyl 4-chloro-3,5-dihydroxyphthalate. Site-selective Suzuki–Miyaura reactions of its bis(triflate) provide a convenient approach to 3,5-diaryl-4-chlorophthalates containing two different aryl groups. [Copyright &y& Elsevier]

Abstract: The TiCl4-mediated formal [3+3] cyclocondensation of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 1,1-dimethoxy-4,4-dichlorobut-1-en-3-one afforded a variety of functionalized 6-dichloromethyl-4-methoxysalicylates with very good regioselectivity. Some of the products were transformed into 6-formyl-4-methoxysalicylates. The employment of Me3SiOTf instead of TiCl4 resulted in a change of the regioselectivity and in the formation of functionalized 2-(dichloromethyl)pyran-4-ones. [Copyright &y& Elsevier]

Abstract: Functionalized 2-(arylthio)benzoates are prepared by formal [3+3] cyclizations of 3-arylthio-1-trimethylsilyloxy-1,3-butadienes with 3-silyloxy-2-en-1-ones and 1,1-diacylcyclopropanes. [Copyright &y& Elsevier]

Abstract: 6-Formylsalicylates are prepared by regioselective [3+3] cyclocondensations of 1,3-bis(silyloxy)-1,3-butadienes with 1,1-dichloro-4-ethoxy-3-buten-2-ones and subsequent transformation of the dichloromethyl into a formyl group. [Copyright &y& Elsevier]

Abstract: A variety of functionalized 5-aryl-3-(trifluoromethyl)phenols were prepared by the first TiCl4-mediated [3+3] cyclocondensation of 1,3-bis(trimethylsilyloxy)-1,3-butadienes with 3-aryl-3-trimethylsilyloxy-1-trifluoromethyl-2-en-1-ones. [Copyright &y& Elsevier]

Abstract: Domino double Heck/electrocyclization/dehydrogenation reactions of 2,3-dibromo-1H-inden-1-one with styrenes provide a convenient synthesis of 2,3-diarylfluorenones. [Copyright &y& Elsevier]

Abstract: The cyclocondensation of 4-chloro-2-oxo-2H-chromene-3-carbaldehyde with 1,3-bis(silyloxy)-1,3-butadienes provides a convenient synthesis of benzo[c]chromen-6-ones. [ABSTRACT FROM AUTHOR]

Abstract: The Suzuki–Miyaura reaction of 1,4-dibromo-2-fluorobenzene with two equivalents of arylboronic acids gave fluorinated para-terphenyls. The reaction with 1equiv of arylboronic acid resulted in site-selective formation of biphenyls. The one-pot reaction of 1,4-dibromo-2-fluorobenzene with two different arylboronic acids afforded fluorinated para-terphenyls containing two different terminal aryl groups. [Copyright &y& Elsevier]

Abstract: The Heck reaction of 2,3-dibromothiophene afforded 2,3-di(alkenyl)thiophenes which were transformed into benzothiophenes by domino ′6π-electrocyclization/dehydrogenation′ reactions. [Copyright &y& Elsevier]

Abstract: Suzuki–Miyaura cross-coupling reactions of tetrabromo-p-benzoquinone provide a convenient approach to tetraaryl-p-benzoquinones. [Copyright &y& Elsevier]

Abstract: Sterically encumbered biaryls are prepared in two steps by CuI-proline-catalyzed arylation of acetylacetone to give 3-arylpentane-2,4-diones and subsequent formal [3+3] cyclization of the latter with 1,3-bis(trimethylsilyloxy)-1,3-dienes. [Copyright &y& Elsevier]

An abstract of the article "Synthesis of 2,3,3a,9a-Tetrahydro-1H-cyclopenta[b]quinoxaline-1,3,4,9-tetracarboxylate by Cyclization of 1,5-Bis[(trimethylsilyl)oxy]penta-1,4-dienes with Quinoxalines" by S. Rotzoll and colleagues is presented.

While the reaction of the anthraquinones (I) and (IV) proceeds with very good selectivity, similar reactions of the compound (VIII) are not selective. [ABSTRACT FROM AUTHOR]

Optimized reaction conditions are developed for the construction of the important scaffold. [ABSTRACT FROM AUTHOR]