Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction ...Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules,especially valuable N-heterocycles.However,successful examples of intermolecular generation ofα-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides.Herein,we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides,enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex-2-ene derivatives in good to excellent yields with excellent diastereoselectivities.Importantly,this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.展开更多
bis(azidomethyl) 3,3′ bis(1,2,4 oxadiazole)(Ⅰ) and bis(azidoacetamino) oxazofurazan(Ⅱ) were synthesized. The structures of these two compounds have been identified by IR, 1H NMR, MS and elemental analy...bis(azidomethyl) 3,3′ bis(1,2,4 oxadiazole)(Ⅰ) and bis(azidoacetamino) oxazofurazan(Ⅱ) were synthesized. The structures of these two compounds have been identified by IR, 1H NMR, MS and elemental analysis. Azido groups were introduced into furazan derivatives and energetic materials of high nitrogen content and high enthalpy of formation can be obtained. The densities of compound Ⅰ and Ⅱ are relatively high. Compound Ⅰ is an azide of lower melting point, it is hopeful to be applied as energetic plastic additives.展开更多
An efficient and mild protocol for bromination of aryl azides with N-bromosuccinimide(NBS) under FeCl_3 catalysis in 1,2- dichloroethane was developed.It is proved to be an efficient method for obtaining brominated ...An efficient and mild protocol for bromination of aryl azides with N-bromosuccinimide(NBS) under FeCl_3 catalysis in 1,2- dichloroethane was developed.It is proved to be an efficient method for obtaining brominated aryl azides.展开更多
Heterocyclic ketene aminals 1 react with aryl azides 2 to give the titled compounds 3,and in some cases also with the formation of fused heterocycles 4.
A mild,efficient and simple method for the preparation of acyl azides from carboxylic acids using chlorodiphenylphosphine in the presence of molecular iodine and sodium azide is described.
The azides were reduced to the corresponding amines by two new metal/Lewis acid systems in water or in aqueous EtOH in yields ranging from 80%-95%. The reaction rates were faster in water than in aqueous EtOH in most...The azides were reduced to the corresponding amines by two new metal/Lewis acid systems in water or in aqueous EtOH in yields ranging from 80%-95%. The reaction rates were faster in water than in aqueous EtOH in most cases. All 16 azides with different functional groups were well reduced to the corresponding amines in excellent yields and reaction rates.展开更多
A simple and efficient process involving the Rh(II)-catalyzed[1+1+3]annulation of diazooxindoles and vinyl azides has been developed for the synthesis of spiropyrrolidine oxindoles with potential biological activity a...A simple and efficient process involving the Rh(II)-catalyzed[1+1+3]annulation of diazooxindoles and vinyl azides has been developed for the synthesis of spiropyrrolidine oxindoles with potential biological activity and significant synthetic applications.This process involves a novel rhodium-catalyzed olefination of diazo compounds,followed by annulation with vinyl azides.This method is compatible with a broad range of substrates and affords moderate to good yields under mild reaction conditions.展开更多
Introduction Glycosyl azides are useful, versatile intermediates for the synthesis of N-glyeosyl derivatives and other biologically important non-carbohydrate derivatives since the azido group can be introduced readil...Introduction Glycosyl azides are useful, versatile intermediates for the synthesis of N-glyeosyl derivatives and other biologically important non-carbohydrate derivatives since the azido group can be introduced readily into aliphatic, aromatic and heterocyclic systems, and can be transformed into other functional groups and utilized for the synthesis of hetero-展开更多
The reagent combination of Hantzsch 1,4-dihydropyridine and Pd/C was found to be an efficient reducing system for the selective reduction of aromatic azides.
The acetylated glycopyranosyl azides were obtained in high yields with stereoselectivity by phase-transfer catalyzed(PTC) synthesis,and their structures were confirmed depending upon elemental analysis and IR,~1H,^(13...The acetylated glycopyranosyl azides were obtained in high yields with stereoselectivity by phase-transfer catalyzed(PTC) synthesis,and their structures were confirmed depending upon elemental analysis and IR,~1H,^(13)C-NMR spectral data.展开更多
Ru(bpy)3]2+-cored supramolecular organic framework SMOF-1, assembled from a [Ru(bpy)3]2+-derived hexaarmed molecule and cucurbit[8]uril, has been demonstrated to heterogeneously catalyze visible light-induced reductio...Ru(bpy)3]2+-cored supramolecular organic framework SMOF-1, assembled from a [Ru(bpy)3]2+-derived hexaarmed molecule and cucurbit[8]uril, has been demonstrated to heterogeneously catalyze visible light-induced reduction of phenyl, benzyl, 2-phenylethyl and 3-phenylpropyl azides in acetonitrile to produce the corresponding amines in good to high yields. For the last two kinds of azides that bear a CO2Me group at the para-position of the benzene ring, cascade reactions take place to generate the corresponding lactams in high yields. Compared with homogeneous control [Ru(bpy)3]Cl2, SMOF-1 exhibits remarkably increased photocatalysis activity as a result of synergistic effect of the [Ru(bpy)3]2+ units that form cubic cages to host the azide molecules and related intermediates. Moreover, SMOF-1 displays high recyclability and considerable photocatalysis activity after 3 to 12 runs.展开更多
In this paper, an efficient synthesis of 5-alkynyl-1,2,3-triazoles through a one-pot aerobic oxidative coupling reaction of various alkynes and azides has been developed. Further derivatization of 5-alkynyl-1,2,3-tria...In this paper, an efficient synthesis of 5-alkynyl-1,2,3-triazoles through a one-pot aerobic oxidative coupling reaction of various alkynes and azides has been developed. Further derivatization of 5-alkynyl-1,2,3-triazoles readily yielded 5-carbonyl-1,2,3-triazoles, 5-carboxylic-1,2,3-triazole, 5-hydroxyalkyl-1,2,3-triazoles and 5-quinoxaline-1,2,3-triazole, which provided an entry into structurally diverse 5-functionalized-1,2,3-triazoles.展开更多
In this article a rapid and facile method for synthesis of acyl azide is described. The cross-linked poly(N-methyl-4- vinylpyridinium) azide ion, [Pa-VP]N3 is prepared and used as an efficient polymeric reagent for ...In this article a rapid and facile method for synthesis of acyl azide is described. The cross-linked poly(N-methyl-4- vinylpyridinium) azide ion, [Pa-VP]N3 is prepared and used as an efficient polymeric reagent for synthesis of acyl azides from acyl halides at room temperature under heterogeneous conditions. Various benzoyl halides, with electron-withdrawing groups as well as electron-donating groups, were transformed into the corresponding benzoyl azides in high to excellent yields in short reaction times. The acyl azide products were characterized by FT-IR, and some of them were also characterized by IH- and/or 13C-NMR spectroscopy, and physical properties were compared to literature values of known compounds. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. Relative to the reported methods, the present method has the advantages of operational simplicity, mild reaction conditions, fast reaction rates, simple reaction work-up and lower hazardous and potentially explosive nature. Also the present method is the first procedure for the synthesis of acyl azides from acyl halides by using a polymer-supported azide ion under heterogeneous conditions.展开更多
A new highly efficient and reusable Cu-MOF has been developed for the regioselective synthesis of 1,2,3-triazoles via the 1,3-dipolar cycloaddition of organic azides to terminal alkynes under solvent-free conditions.T...A new highly efficient and reusable Cu-MOF has been developed for the regioselective synthesis of 1,2,3-triazoles via the 1,3-dipolar cycloaddition of organic azides to terminal alkynes under solvent-free conditions.This protocol has the advantages of excellent product yields and a low catalyst loading.Moreover,the catalyst may be recovered and reused efficiently up to 5 cycles without major loss of reactivity.展开更多
An efficient method for the three-component azidopyridylation of unactivated alkenes to accessβ-pyridyl azides has been developed.The overall process involves a visible light-mediated radical-relay sequence that begi...An efficient method for the three-component azidopyridylation of unactivated alkenes to accessβ-pyridyl azides has been developed.The overall process involves a visible light-mediated radical-relay sequence that begins with an in situ generated methoxy radical,which may facilitate Si-N_(3) bond activation to generate azidyl radical under mild conditions.The ensuing azidyl radical adds to the alkenes to furnish the carbon-centered radicals which themselves add,in an intermolecular sense,to pyridinium salts.This three-component photocatalytic strategy is effective for a broad range of alkenes and N-heterocycles,and readily affords synthetically useful azidyl-and pyridyl-containing building blocks.This method provides new insights into methoxy radical-initiated relay reactions as well as access to a range of new molecular scaffolds.展开更多
1,3-Difluorinated molecules featuring fluorinecontaining stereocenters often exhibit intriguing conformational properties attributed to 1,3-dipolar minimization effects.Here,we describe a diastereoselective synthesis ...1,3-Difluorinated molecules featuring fluorinecontaining stereocenters often exhibit intriguing conformational properties attributed to 1,3-dipolar minimization effects.Here,we describe a diastereoselective synthesis of 1,3-difluoro-2-azides bearing three contiguous stereocenters via hypervalent iodine-mediated migratory 1,3-difluorination of allylic azides with Olah’s reagent.This reaction represents a substrate-controlled diastereoselective fluorination in hypervalent iodine/HF system for the first time.Computational studies suggest that the crucial coordination of the azido group with iodine(III)species accounts for the observed high diastereoselectivity.The analysis of crystal structures of several of the products,along with their nonfluorinated counterparts,consistently reveals the impact of 1,3-difluorides in determining molecular conformation.Furthermore,the postsynthetic utility of this methodology is showcased by a gram-scale synthesis and various value-added manipulations of the retained azido functionality.展开更多
基金financial support from the National Natural Science Foundation of China(Nos.22125108,22331004 and 22121001)Yunnan Normal University,Applied Basic Research Projects of Yunnan Province(No.202101AT070217)+1 种基金the Jiangxi Provincial Natural Science Foundation(No.20224BAB213013)the Jiangxi Provincial Department of Education in Science and Technology Program Project(No.GJJ210906)。
文摘Gold-catalyzed amination reactions based on azides viaα-imino gold carbene intermediates have attracted extensive attention in the past decades because this methodology leads to the facile and efficient construction of synthetically useful N-containing molecules,especially valuable N-heterocycles.However,successful examples of intermolecular generation ofα-imino gold carbenes by using azides as amination reagents are rarely explored probably due to the weak nucleophilicity of azides.Herein,we disclose an efficient gold-catalyzed intermolecular aminative cyclopropanation of ynamides with the allyl azides,enabling flexible synthesis of a wide range of valuable 3-azabicyclo[3.1.0]hex-2-ene derivatives in good to excellent yields with excellent diastereoselectivities.Importantly,this protocol represents the first use of allyl azide as an efficient amination reagent in gold-catalyzed alkyne amination reactions.
文摘bis(azidomethyl) 3,3′ bis(1,2,4 oxadiazole)(Ⅰ) and bis(azidoacetamino) oxazofurazan(Ⅱ) were synthesized. The structures of these two compounds have been identified by IR, 1H NMR, MS and elemental analysis. Azido groups were introduced into furazan derivatives and energetic materials of high nitrogen content and high enthalpy of formation can be obtained. The densities of compound Ⅰ and Ⅱ are relatively high. Compound Ⅰ is an azide of lower melting point, it is hopeful to be applied as energetic plastic additives.
基金supported by National Natural Science Foundation of China(No30873153)the Key Projects of Shanghai in Biomedical(No08431902700)the Scientific Research Foundation of State Education Ministry for the Returned Overseas Chinese Scholars
文摘An efficient and mild protocol for bromination of aryl azides with N-bromosuccinimide(NBS) under FeCl_3 catalysis in 1,2- dichloroethane was developed.It is proved to be an efficient method for obtaining brominated aryl azides.
文摘Heterocyclic ketene aminals 1 react with aryl azides 2 to give the titled compounds 3,and in some cases also with the formation of fused heterocycles 4.
基金the Persian Gulf University Research Council for generous partial financial support of this study
文摘A mild,efficient and simple method for the preparation of acyl azides from carboxylic acids using chlorodiphenylphosphine in the presence of molecular iodine and sodium azide is described.
文摘The azides were reduced to the corresponding amines by two new metal/Lewis acid systems in water or in aqueous EtOH in yields ranging from 80%-95%. The reaction rates were faster in water than in aqueous EtOH in most cases. All 16 azides with different functional groups were well reduced to the corresponding amines in excellent yields and reaction rates.
基金supported by the National Natural Science Foundation of China(21572225)~~
文摘A simple and efficient process involving the Rh(II)-catalyzed[1+1+3]annulation of diazooxindoles and vinyl azides has been developed for the synthesis of spiropyrrolidine oxindoles with potential biological activity and significant synthetic applications.This process involves a novel rhodium-catalyzed olefination of diazo compounds,followed by annulation with vinyl azides.This method is compatible with a broad range of substrates and affords moderate to good yields under mild reaction conditions.
基金Supported by the National Natural Science Foundation of China
文摘Introduction Glycosyl azides are useful, versatile intermediates for the synthesis of N-glyeosyl derivatives and other biologically important non-carbohydrate derivatives since the azido group can be introduced readily into aliphatic, aromatic and heterocyclic systems, and can be transformed into other functional groups and utilized for the synthesis of hetero-
基金the National Natural Science Foundation of China(No.20772053)Natural Science Foundation of Gansu Province(No.3ZS061-A25-004)for financial support.
文摘The reagent combination of Hantzsch 1,4-dihydropyridine and Pd/C was found to be an efficient reducing system for the selective reduction of aromatic azides.
文摘The acetylated glycopyranosyl azides were obtained in high yields with stereoselectivity by phase-transfer catalyzed(PTC) synthesis,and their structures were confirmed depending upon elemental analysis and IR,~1H,^(13)C-NMR spectral data.
基金supported by the National Natural Science Foundation of China (Nos. 21432004 and 21890732)
文摘Ru(bpy)3]2+-cored supramolecular organic framework SMOF-1, assembled from a [Ru(bpy)3]2+-derived hexaarmed molecule and cucurbit[8]uril, has been demonstrated to heterogeneously catalyze visible light-induced reduction of phenyl, benzyl, 2-phenylethyl and 3-phenylpropyl azides in acetonitrile to produce the corresponding amines in good to high yields. For the last two kinds of azides that bear a CO2Me group at the para-position of the benzene ring, cascade reactions take place to generate the corresponding lactams in high yields. Compared with homogeneous control [Ru(bpy)3]Cl2, SMOF-1 exhibits remarkably increased photocatalysis activity as a result of synergistic effect of the [Ru(bpy)3]2+ units that form cubic cages to host the azide molecules and related intermediates. Moreover, SMOF-1 displays high recyclability and considerable photocatalysis activity after 3 to 12 runs.
基金the NSFC (Nos. 21172058, 20802017)HASTIT (No. 2012HASTIT10)+1 种基金PCSIRT (No. IRT1061)Key Technologies R & D Program of Henan Province (No. 112102310319) for financial support
文摘In this paper, an efficient synthesis of 5-alkynyl-1,2,3-triazoles through a one-pot aerobic oxidative coupling reaction of various alkynes and azides has been developed. Further derivatization of 5-alkynyl-1,2,3-triazoles readily yielded 5-carbonyl-1,2,3-triazoles, 5-carboxylic-1,2,3-triazole, 5-hydroxyalkyl-1,2,3-triazoles and 5-quinoxaline-1,2,3-triazole, which provided an entry into structurally diverse 5-functionalized-1,2,3-triazoles.
文摘In this article a rapid and facile method for synthesis of acyl azide is described. The cross-linked poly(N-methyl-4- vinylpyridinium) azide ion, [Pa-VP]N3 is prepared and used as an efficient polymeric reagent for synthesis of acyl azides from acyl halides at room temperature under heterogeneous conditions. Various benzoyl halides, with electron-withdrawing groups as well as electron-donating groups, were transformed into the corresponding benzoyl azides in high to excellent yields in short reaction times. The acyl azide products were characterized by FT-IR, and some of them were also characterized by IH- and/or 13C-NMR spectroscopy, and physical properties were compared to literature values of known compounds. The spent polymeric reagents can be regenerated and reused for several times without losing their activity. Relative to the reported methods, the present method has the advantages of operational simplicity, mild reaction conditions, fast reaction rates, simple reaction work-up and lower hazardous and potentially explosive nature. Also the present method is the first procedure for the synthesis of acyl azides from acyl halides by using a polymer-supported azide ion under heterogeneous conditions.
基金financial support for this research from the Welch Foundation(grant no.AX-1593)the NIHNIGMS(grant no.SC1GM082718)the financial support for this research from the Welch Foundation(grant no.AX-1730).
文摘A new highly efficient and reusable Cu-MOF has been developed for the regioselective synthesis of 1,2,3-triazoles via the 1,3-dipolar cycloaddition of organic azides to terminal alkynes under solvent-free conditions.This protocol has the advantages of excellent product yields and a low catalyst loading.Moreover,the catalyst may be recovered and reused efficiently up to 5 cycles without major loss of reactivity.
基金Guangdong Basic and Applied Basic Research Foundation(Nos.2022A1515110367,2024A1515010884)the National Natural Science Foundation of China(No.22201104)the Science and Technology Projects in Guangzhou(No.2023A04J0079)for financial support。
文摘An efficient method for the three-component azidopyridylation of unactivated alkenes to accessβ-pyridyl azides has been developed.The overall process involves a visible light-mediated radical-relay sequence that begins with an in situ generated methoxy radical,which may facilitate Si-N_(3) bond activation to generate azidyl radical under mild conditions.The ensuing azidyl radical adds to the alkenes to furnish the carbon-centered radicals which themselves add,in an intermolecular sense,to pyridinium salts.This three-component photocatalytic strategy is effective for a broad range of alkenes and N-heterocycles,and readily affords synthetically useful azidyl-and pyridyl-containing building blocks.This method provides new insights into methoxy radical-initiated relay reactions as well as access to a range of new molecular scaffolds.
基金supported by the National Natural Science Foundation of China(grant no.22171293)the Guangdong Basic and Applied Basic Research Foundation(grant no.2024A1515012178)the Guangdong Provincial Key Laboratory of Construction Foundation(grant no.2023B1212060022).
文摘1,3-Difluorinated molecules featuring fluorinecontaining stereocenters often exhibit intriguing conformational properties attributed to 1,3-dipolar minimization effects.Here,we describe a diastereoselective synthesis of 1,3-difluoro-2-azides bearing three contiguous stereocenters via hypervalent iodine-mediated migratory 1,3-difluorination of allylic azides with Olah’s reagent.This reaction represents a substrate-controlled diastereoselective fluorination in hypervalent iodine/HF system for the first time.Computational studies suggest that the crucial coordination of the azido group with iodine(III)species accounts for the observed high diastereoselectivity.The analysis of crystal structures of several of the products,along with their nonfluorinated counterparts,consistently reveals the impact of 1,3-difluorides in determining molecular conformation.Furthermore,the postsynthetic utility of this methodology is showcased by a gram-scale synthesis and various value-added manipulations of the retained azido functionality.