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A facile synthesis of novel 3-functionalized pyridine derivatives has been accomplished through the reaction of 4-hydroxy-3-benzoylpyridin-2(1H)-ones and β-nitrostyrenes in the presence of catalytic amount of pyrrolidine (10 mol%). In this process, the desired products were obtained with 72–87% yields using ethanol as solvent at 80 °C for 4 h. In addition, a total of 19 examples were obtained, which exhibited the broad substrate scope of the transformation. The reaction process may involve the formation of an unstable enamine intermediate and then undergo hydrolysis to afford 4-hydroxy-3-benzoylpyridin-2(1H)-one derivatives. [ABSTRACT FROM AUTHOR]

A catalyst‐free protocol for synthesizing a new series of indeno[1,2‐b][1,6]naphthyridine‐1,10(2H)‐dione derivatives with good to excellent yields was established based on microwave‐assisted domino reaction of 4‐aminopyridin‐2(1H)‐ones, aldehydes and 1H‐indene‐1,3(2H)‐dione in water. The present approach exhibited useful and green features, such as water as reaction solvent, catalyst‐ and additive‐ free, short reaction time (20–30 min), as well as ease of desired products separation and purification without the need for column chromatography. Also to note, up to four new bonds were formed accompanied by generating water as sole by‐product in this one‐pot procedure. [ABSTRACT FROM AUTHOR]

The mesoporous silica SAB‐15 material and a series of nano‐composite bimetal oxides‐SBA‐15 materials are synthesized. The oxidation of various benzyl alcohols to aromatic aldehydes has been studied using nano‐composite bimetal oxides‐SBA‐15 materials as catalysts in air. The results indicate that the CrMnOx‐SBA‐15 material can promote the oxidation of benzyl alcohols to aromatic aldehydes with excellent yields smoothly. The microstructure and morphology of SBA‐15 and CrMnOx‐SBA‐15 materials are characterized by SEM, TEM, XRD and nitrogen adsorption/desorption isotherms, respectively. In addition, the UHRTEM images, EDS image mapping, and the X‐ray photoelectron spectroscopy (XPS) of CrMnOx‐SBA‐15 material also are characterized, which indicate the structure of the catalyst is advantageous to improve its catalytic activity. [ABSTRACT FROM AUTHOR]

A three-component domino reaction for the synthesis of naphtho[2,3- b ][1,6]naphthyridine derivatives has been established. Such strategy exhibited excellent substrate scope including various enaminones and aldehydes that afforded a series of multifunctionalized naphtho[2,3- b ][1,6]naphthyridine derivatives with 70–86% yields. The advantages of bond-forming efficiency, accessibility of starting materials, and water as sole byproducts provide invaluable access to biological 1,6-naphthyridines. [ABSTRACT FROM AUTHOR]

Abstract: A series of poly‐substituted pyrano[2,3–d]pyrimidine derivatives have been synthesized using solid acid as catalyst in water. The poly‐substituted pyrano[2,3–d]pyrimidines are important structural motifs in organic and biological research. The present procedure shows many attractive advantages, such as the operational simplicity, highly efficiency and recyclability of heterogeneous catalyst, and highly yields of desired products. A probable mechanism was proposed for accounting the domino reaction. [ABSTRACT FROM AUTHOR]

An efficient domino approach for the synthesis of new pyrano[4,3- b ]pyrazolo[4,3- e ]pyridin-5(1 H )-one derivatives has been developed using reusable sulfonic organic resin as catalyst in water. The unique feature of sulfonic organic resin makes the formation of pyrano[4,3- b ]pyrazolo[4,3- e ] pyridin-5(1 H )-ones be possible, and avoids generating ring opening products. The plausible mechanism for this domino reaction is proposed. [ABSTRACT FROM AUTHOR]

A series of furo[2,3- d ]pyrimidine derivatives were synthesized via the [3+2] cyclization of pyrimidine-4,6-diol and a variety of nitroolefins at catalyst-free conditions. The reaction is easy to perform simply mixing inexpensive starting materials in water under conventional heating at 90 °C. The reaction proceeds at a fast speed within 1.5–2 h and gives the high biological and pharmacological active substituent furo[2,3- d ]pyrimidine derivatives with good to high yields. Mechanism of formation of these furo[2,3- d ]pyrimidine derivatives are also proposed. [ABSTRACT FROM AUTHOR]

A solid acid-catalyzed cascade reaction of condensation/intermolecular nucleophilic addition/intramolecular cyclization, esterification and amination has been developed to rapidly construct complex polysubstituted indole compounds. This one-pot, three-step five-component cascade reaction affords a series of 2-(4-oxo-1,2-diphenyl-4,5,6,7-tetrahydro-1 H -indol-3-yl) acetamide derivatives with good yield under mild conditions. The present procedure exhibited some attractive features, including inexpensive and easy available reagents, large substrate scope, separable intermediate products, recyclable solid acid catalyst, and more importantly, it can be conveniently performed by simple one-pot three-step procedure, involving the sequential mixture of 3-(arylamino)cyclohex-2-en-1-ones, 2,2-dihydroxy-1-arylethan-1-ones, meldrum acid, and alcohols, anilines in the of solid acid at 80 °C. Significantly, this strategy not only expands the application range of solid acid, but also provides a series of 2-(4-oxo-1,2-diphenyl-4,5,6,7-tetrahydro-1 H -indol-3-yl)acetate/acetamide derivatives. [Display omitted] • A one-pot three-step reaction for the synthesis of indol-3-yl acetamides has been reported. • The reaction can be performed using recyclable solid acid as catalyst in water. • This chemistry provides a strategy to synthesize indol-3-yl acetates and indol-3-yl acetamides. [ABSTRACT FROM AUTHOR]

Abstract: A new series of organo-titanium complexes have been prepared from the reaction between Ti(NMe2)4 and C 2-symmetric ligands, (R,R)-11,12-bis(pyrrol-2-ylmethyleneamino)-9,10-dihydro-9,10-ethanoanthracene (1H2), and (R,R)-bis(diphenylthiophosphoramino)-9,10-dihydro-9,10-ethanoanthracene (2H2), (R,R)-11,12-bis(mesitylenesulphonylamino)-9,10-dihydro-9,10-ethanoanthracene (3H2) and (R,R)-bis(diphenylthiophosphoramino)-1,2-cyclohexane (4H2). Treatment of Ti(NMe2)4 with 1 equiv of 1H2 gives, after recrystallization from a benzene solution, the binuclear double helicate titanium amide (1)2[Ti(NMe2)2]2⋅(5) in 71% yield. While under similar reaction conditions, reaction of Ti(NMe2)4 with 1equiv of 2H2, 3H2 or 4H2 gives, after recrystallization from a toluene or benzene solution, the mononuclear single helicate titanium amides (2)Ti(NMe2)2 (6), (3)Ti(NMe2)2 (7) and (4)Ti(NMe2)2 (8), respectively, in good yields. All new compounds have been characterized by various spectroscopic techniques, and elemental analyses. The solid-state structures of complexes 5–8 have further been confirmed by X-ray diffraction analyses. The titanium amides are active catalysts for the polymerization of rac-lactide, leading to the isotactic-rich polylactides. [Copyright &y& Elsevier]

Abstract: Five group 4 metal complexes (1)2Zr(NMe2)2 (5), (2)2Ti(NMe2)2 (6), (2)2Zr(NMe2)2 (7), (3)2Zr (8) and (4)2Ti(NMe2)2 (9) have been readily prepared from the reaction between M(NMe2)4 (M=Ti, Zr) and chiral binaphthyldiamine-based ligands, (R)-2,2′-bis(diphenylthiophosphoramino)-1,1′-binaphthyl (1H2), (R)-5,5′,6,6′,7,7′,8,8′-octahydro-2,2′-bis(diphenylthiophosphoramino)-1,1′-binaphthyl (2H2), (R)-5,5′,6,6′,7,7′,8,8′-octahydro-2,2′-bis(methanesulphonylamino)-1,1′-binaphthyl (3H2), and C 1-symmetric ligand, (R)-2-(mesitylenesulphonylamino)-2′-(dimethylamino)-1,1′-binaphthyl (4H). All the complexes have been characterized by various spectroscopic techniques, elemental analyses and X-ray diffraction analyses. The zirconium amides are active catalysts for the asymmetric hydroamination/cyclization of aminoalkenes, affording cyclic amines in good yields with moderate ee (enantiomeric excess) values. [Copyright &y& Elsevier]

Abstract: A new series of titanium(IV) and zirconium(IV) amides have been prepared from the reaction between M(NMe2)4 (M=Ti, Zr) and C 2-symmetric ligands, (R)-2,2′-bis(pyridin-2-ylmethylamino)-6,6′-dimethyl-1,1′-biphenyl (2H2), (R)-2,2′-bis(pyrrol-2-ylmethyleneamino)-6,6′-dimethyl-1,1′-biphenyl (3H2), (R)-2,2′-bis(diphenylphosphinoylamino)-6,6′-dimethyl-1,1′-biphenyl (4H2), (R)-2,2′-bis(methanesulphonylamino)-6,6′-dimethyl-1,1′-biphenyl (5H2), (R)-2,2′-bis(p-toluenesulphonylamino)-6,6′-dimethyl-1,1′-biphenyl (6H2), and C 1-symmetric ligands, (R)-2-(diphenylthiophosphoramino)-2′-(dimethylamino)-6,6′-dimethyl-1,1′-biphenyl (7H) and (R)-2-(pyridin-2-ylamino)-2′-(dimethylamino)-6,6′-dimethyl-1,1′-biphenyl (8H), which are derived from (R)-2,2′-diamino-6,6′-dimethyl-1,1′-biphenyl. Treatment of M(NMe2)4 with 1 equiv. of N4-ligand, 2H2 or 3H2 gives, after recrystallization from an n-hexane solution, the chiral zirconium amides (2)Zr(NMe2)2 (9), (3)Zr(NMe2)2 (11), and titanium amide (3)Ti(NMe2)2 (10), respectively, in good yields. Reaction of Zr(NMe2)4 with 1 equiv of diphenylphosphoramide 4H2 affords the chiral zirconium amide (4)Zr(NMe2)2 (12) in 85% yield. Under similar reaction conditions, treatment of Ti(NMe2)4 with 1 equiv. of sulphonylamide ligand, 5H2 or 6H2 gives, after recrystallization from a toluene solution, the chiral titanium amides (5)Ti(NMe2)2·0.5C7H8 (13·0.5C7H8) and (6)Ti(NMe2)2 (15), respectively, in good yields, while reaction of Zr(NMe2)4 with 1 equiv. of 5H2 or 6H2 gives the bis-ligated complexes, (5)2Zr (14) and (6)2Zr (16). Treatment of M(NMe2)4 with 2 equiv. of diphenylthiophosphoramide ligand 7H or N3-ligand 8H gives, after recrystallization from a benzene solution, the bis-ligated chiral zirconium amides (7)2Zr(NMe2)2 (17) and (8)2Zr(NMe2)2 (19), and bis-ligated chiral titanium amide (8)2Ti(NMe2)2 (18), respectively, in good yields. All new compounds have been characterized by various spectroscopic techniques, and elemental analyses. The solid-state structures of complexes 10, 12, 13, and 17–19 have further been confirmed by X-ray diffraction analyses. The zirconium amides are active catalysts for the asymmetric hydroamination/cyclization of aminoalkenes, affording cyclic amines in good to excellent yields with moderate ee values, while the titanium amides are not. [Copyright &y& Elsevier]

A concise and efficient addition reaction of alcohol to β -nitrostyrene promoted by Y(OTf) 3 has been established for the synthesis of β -nitroether derivatives. The present approach shows attractive properties, such as the high efficiency of catalyst, operational simplicity, and the tolerance of a wide range of functional groups. This strategy not only provides a variety of β -nitroethers but also expands the scope of application of early transition metals. [ABSTRACT FROM AUTHOR]

An efficient, high yielding method has been developed for the synthesis of diversity tetrahydro-4 H -indol-4-one derivatives via a three component, one pot domino reaction from cyclohexane-1,3-diones, amines and nitrostyrenes using carbon functionalized with sulfonic acid group carbonaceous material as catalyst for the first time. The reaction was carried out in water, affording good to excellent yields in short time. The advantages of atom and step economy, green, and scope make this reaction a powerful tool for assembling heterocyclic scaffolds of general chemical and biomedical interest. [ABSTRACT FROM AUTHOR]

O /S-Based heterocycles have emerged as one of the most important classes of heterocyclic compounds and have received considerable attention because of their importance as 'privileged pharmacological structures' widely distributed in natural products and active pharmaceutical ingredients. As a testament to this, a plethora of methods for the synthesis of these O / S -heterocycles have been disclosed. Of particular importance in the blossoming field are multicomponent approaches using β -nitrostyrenes as starting materials via domino processes. This review introduces recent strategies for the creation of O / S -heterocycles from β -nitrostyrenes and the corresponding partners. Particular attention has been given to the advancement and limitation of approximately 50 studies concerning the preparation of these heterocycles, with a focus from 2014 to 2023. To create your abstract, type over the instructions in the template box below. Fonts or abstract dimensions should not be changed or altered. [Display omitted] • A plethora of methods for the synthesis of O / S -heterocycles have been disclosed. • This review introduces recent strategies for the creation of O / S -heterocycles from β -nitrostyrenes. • About 50 studies for synthesis of O / S -heterocycles published from 2014 to 2023 are reviewed. [ABSTRACT FROM AUTHOR]

• An efficient and green strategy for synthesis of 1,6-naphthyridines has been established. • The 1,6-naphthyridines are obtained catalyzed by solid acid under ultrasonic irradiation. • The ultrasonic irradiation as thermal and kinetic energy source shorten reaction time and heighten yield. An efficient and highly eco-friendly approach to poly-substituted 1,6-naphthyridine derivatives with good to excellent yield has been reported using simple and readily available 4-aminopyridinone, aromatic aldehyde or isatin, and 1,3-cyclohexanedione as substrates. The method features low-cost and readily accessible starting materials, green ultrasonic irradiation in water, recycle heterogeneous solid acid catalyst, broad substrate scope as well as simple one-pot operation make this strategy highly attractive. Mechanistic studies indicate that this transformation involves Knoevenagel condensation, Michael addition, and cyclization sequence. [ABSTRACT FROM AUTHOR]

A simple and efficient procedure for the synthesis of pyrazoloisoquinoline and pyrazolopyridine derivatives by one-pot three-component condensation of aminopyrazoles, aldehydes, and cycloketones in water using carbonaceous material as solid acid catalyst is described. The procedure offers several advantages such as simple experimental and work-up procedures, high yield, recovery, and reusability of metal-free solid acid heterogeneous catalyst along with tolerance of a wide range of functional groups. [ABSTRACT FROM AUTHOR]

• A new domino approach for synthesis of pyrrolo[3,2- c pyridin-4-ones has been established. • The one-pot two-step four component strategy makes the reaction attractive. • The remarkable feature of the process is the formation of five C–N, C–C bonds initiated by sole acetic acid. A direct and metal-free access toward poly-substituted pyrrolo[3,2- c pyridin-4-one and its analogues have been established through a simple four-component, two-step reaction of 4-hydroxy-6-methyl-2 H -pyran-2-one, two amine molecules, and β -nitrostyrenes. The reaction allows the formation of five different C–N, C–C bonds by the multiple bond cleavage only using acetic acid as catalyst and solvent. The advantages of broad substrate scope, efficient and metal-free reaction conditions, inexpensive and readily available starting materials as well as simple one-pot two-step operation, make the strategy highly attractive. This transformation in acetic acid resulted in the rapid establishment of functional bioactive poly-substituted pyrrolo[3,2- c pyridin-4-one derivatives. [ABSTRACT FROM AUTHOR]