We describe a convenient method for the synthesis of 1,2-disubstituted acetylenes via a cross-coupling reaction of (bromoethynyl)benzene with Grignard reagents. The reaction of (bromoethynyl)benzene (1 mmol) wit...We describe a convenient method for the synthesis of 1,2-disubstituted acetylenes via a cross-coupling reaction of (bromoethynyl)benzene with Grignard reagents. The reaction of (bromoethynyl)benzene (1 mmol) with Grignard reagent (1.3 mmol) mediated by NiCl2 (4 mol%) and (p-CH3Ph)3P (8 mol%) in THF could produce 1,2-disubstituted acetylenes in good yields at room temperature.展开更多
Sterically congested 2,2-disubstituted indane-1,3-dione derivatives have been syn-thesized and characterized by 1H NMR,13C NMR,FT-IR and elemental analysis.The B3LYP/HF calculations for computation of IR spectra have ...Sterically congested 2,2-disubstituted indane-1,3-dione derivatives have been syn-thesized and characterized by 1H NMR,13C NMR,FT-IR and elemental analysis.The B3LYP/HF calculations for computation of IR spectra have been carried out for the title compounds at the 6-31G and 6-311++G basis set levels.Predicted vibrational frequencies have been assigned and compared with the experimental FT-IR spectra and they are supported each other.展开更多
A strategy for the synthesis of 1,2-disubstituted benzimidazoles has been developed and a variety of 1,2-disubstituted benzimidazoles were obtained from imidoyl chlorides and o-haloanilines via copper(I)-catalyzed r...A strategy for the synthesis of 1,2-disubstituted benzimidazoles has been developed and a variety of 1,2-disubstituted benzimidazoles were obtained from imidoyl chlorides and o-haloanilines via copper(I)-catalyzed reaction in moderate yields.展开更多
1,2-Disubstituted benzimidazoles are selectively synthesized in high yields under extremely mild conditions via the condensation of o-phenylenediamine derivatives with aldehyde derivatives using catalytic amount of i...1,2-Disubstituted benzimidazoles are selectively synthesized in high yields under extremely mild conditions via the condensation of o-phenylenediamine derivatives with aldehyde derivatives using catalytic amount of iron(Ⅲ) phosphate under solventfree conditions. The use of readily available iron(Ⅲ) phosphate as a reusable and recyelable catalyst makes this process quite simple, convenient, and environment-friendly.展开更多
Reaction of polymer-supported a-selenoaldehydes with Grignard reagents afforded polymer-bound B-hydroxyalkyl selenides, which treated with thionyl chloride and triethylamine leading to (E)-1, 2-disubstituted ethenes i...Reaction of polymer-supported a-selenoaldehydes with Grignard reagents afforded polymer-bound B-hydroxyalkyl selenides, which treated with thionyl chloride and triethylamine leading to (E)-1, 2-disubstituted ethenes in good yield.展开更多
La[N(SiMe3)2]3 proves to be an efficient catalyst system for the cyclocarbonylation of 1,2-disubstituted benzenes with isocyanates. In this approach, aryl/alkyl isocyanates react with o-phenylenediamine, o-aminophenol...La[N(SiMe3)2]3 proves to be an efficient catalyst system for the cyclocarbonylation of 1,2-disubstituted benzenes with isocyanates. In this approach, aryl/alkyl isocyanates react with o-phenylenediamine, o-aminophenol, o-aminothiophenol, catechols and anilines ortho-substituted by CH2NH2 and CONH2 to form, respectively, the corresponding benzimidazolones, benzoxazolones, benzothiazolones, benzodioxolones, 3,4-dihydroquinazolin-2(1H)-one, and quinazolinediones. These results represent the first example of lanthanide-catalyzed carbonylation. This methodology is also applicable for the preparation of various benzannulated 1,3-diheteroatom cyclic thioketones starting from aryl/alkyl isothiocyanates or CS2 in good to excellent yields. Based on the results of experiments performed using an o-aminobenzamido dianion lanthanide complex, a general mechanism, involving the tandem reaction of two lanthanide-ligand bonds with one heterocumulene molecule, is proposed as well.展开更多
A facile synthesis of 2,2-disubstituted idanes was achieved by the reductive cyclization of 1-(o-bromomethylphenyl)-2,2-disubstituted-ethylenes(electron-withdrawing substituents) with an NAD(P)H model, 1-benzyl-1,4-di...A facile synthesis of 2,2-disubstituted idanes was achieved by the reductive cyclization of 1-(o-bromomethylphenyl)-2,2-disubstituted-ethylenes(electron-withdrawing substituents) with an NAD(P)H model, 1-benzyl-1,4-dihydronicotinamide, in yields from moderate to good. The study revealed that \{1-benzyl\}-1,4-dihydronicotinamide can be used in synthetic organic chemistry as an effective reductant.展开更多
This letter describes a method for the stereoselective synthesis of polymer supported vinylic selenides and their applications to synthesis of ( E ) and ( Z ) 1,2 disubstituted ethenes on solid phase by the ...This letter describes a method for the stereoselective synthesis of polymer supported vinylic selenides and their applications to synthesis of ( E ) and ( Z ) 1,2 disubstituted ethenes on solid phase by the coupling reaction with Grignard reagents under the catalysis of NiCl 2(PPh 3) 2.展开更多
基金financially supported by the Fundamental Research Funds for the Central Universities,Southwest University for Nationalities (No.12NZYTH03)the Natural Science Foundation of Southwest University for Nationalities (No.381010)+1 种基金the Project of Postgraduate Degree Construction,Southwest University for Nationalities (No.2013XWD-S0703)the State Administration of Foreign Experts Affairs project (No.2012-10)
文摘We describe a convenient method for the synthesis of 1,2-disubstituted acetylenes via a cross-coupling reaction of (bromoethynyl)benzene with Grignard reagents. The reaction of (bromoethynyl)benzene (1 mmol) with Grignard reagent (1.3 mmol) mediated by NiCl2 (4 mol%) and (p-CH3Ph)3P (8 mol%) in THF could produce 1,2-disubstituted acetylenes in good yields at room temperature.
文摘Sterically congested 2,2-disubstituted indane-1,3-dione derivatives have been syn-thesized and characterized by 1H NMR,13C NMR,FT-IR and elemental analysis.The B3LYP/HF calculations for computation of IR spectra have been carried out for the title compounds at the 6-31G and 6-311++G basis set levels.Predicted vibrational frequencies have been assigned and compared with the experimental FT-IR spectra and they are supported each other.
文摘A strategy for the synthesis of 1,2-disubstituted benzimidazoles has been developed and a variety of 1,2-disubstituted benzimidazoles were obtained from imidoyl chlorides and o-haloanilines via copper(I)-catalyzed reaction in moderate yields.
文摘1,2-Disubstituted benzimidazoles are selectively synthesized in high yields under extremely mild conditions via the condensation of o-phenylenediamine derivatives with aldehyde derivatives using catalytic amount of iron(Ⅲ) phosphate under solventfree conditions. The use of readily available iron(Ⅲ) phosphate as a reusable and recyelable catalyst makes this process quite simple, convenient, and environment-friendly.
基金Project 29932020 was supported by the National Natural Science Foundation of China.
文摘Reaction of polymer-supported a-selenoaldehydes with Grignard reagents afforded polymer-bound B-hydroxyalkyl selenides, which treated with thionyl chloride and triethylamine leading to (E)-1, 2-disubstituted ethenes in good yield.
基金supported by the National Natural Science Foundation of China (21132002, 21272038)the National Basic Research Program of China (2011CB825300)
文摘La[N(SiMe3)2]3 proves to be an efficient catalyst system for the cyclocarbonylation of 1,2-disubstituted benzenes with isocyanates. In this approach, aryl/alkyl isocyanates react with o-phenylenediamine, o-aminophenol, o-aminothiophenol, catechols and anilines ortho-substituted by CH2NH2 and CONH2 to form, respectively, the corresponding benzimidazolones, benzoxazolones, benzothiazolones, benzodioxolones, 3,4-dihydroquinazolin-2(1H)-one, and quinazolinediones. These results represent the first example of lanthanide-catalyzed carbonylation. This methodology is also applicable for the preparation of various benzannulated 1,3-diheteroatom cyclic thioketones starting from aryl/alkyl isothiocyanates or CS2 in good to excellent yields. Based on the results of experiments performed using an o-aminobenzamido dianion lanthanide complex, a general mechanism, involving the tandem reaction of two lanthanide-ligand bonds with one heterocumulene molecule, is proposed as well.
文摘A facile synthesis of 2,2-disubstituted idanes was achieved by the reductive cyclization of 1-(o-bromomethylphenyl)-2,2-disubstituted-ethylenes(electron-withdrawing substituents) with an NAD(P)H model, 1-benzyl-1,4-dihydronicotinamide, in yields from moderate to good. The study revealed that \{1-benzyl\}-1,4-dihydronicotinamide can be used in synthetic organic chemistry as an effective reductant.
基金theNationalNaturalScienceFoundationofChina (No .2 993 2 0 2 0 )
文摘This letter describes a method for the stereoselective synthesis of polymer supported vinylic selenides and their applications to synthesis of ( E ) and ( Z ) 1,2 disubstituted ethenes on solid phase by the coupling reaction with Grignard reagents under the catalysis of NiCl 2(PPh 3) 2.