Acylsilanes are versatile building blocks widely used in organic transformations.However,the current synthetic approaches require multiple steps,as well as the use of silyl metals or sensitive reagents or copious amou...Acylsilanes are versatile building blocks widely used in organic transformations.However,the current synthetic approaches require multiple steps,as well as the use of silyl metals or sensitive reagents or copious amounts of transition-metal catalysts,complex ligands,and elevated temperatures.In this study,a novel visible-light-mediated,metal-free approach for generating silyl acyl radical intermediates via the reaction of silyl radicals and CO is reported.By trapping the species with various reagents,a wide range of acylsilanes could be accessed smoothly under mild conditions,with high atom economy.Gramscale synthesis could be easily achieved using continuous-flow reactors,indicating the potential for industrial-scale manufacturing and enhanced process safety.Furthermore,these generated acylsilanes could be employed in synthesizing valuable skeletons such asα-alkoxyorganoboronate esters,cyclopropanes,modified tryptophan-containing oligopeptides,andα-silyl alcohols through simple transformations.We anticipate that this strategy would be universally applicable for constructing diverse acylsilanes and complement current catalysis methodologies.展开更多
Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material chemistry.In this review,we summarize the investigations on the synthesis of organofluorine compounds ...Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material chemistry.In this review,we summarize the investigations on the synthesis of organofluorine compounds with acylsilanes.For the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-difluoroketones.For the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine compounds.In general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.展开更多
Imposing conformational constraints on sp3-rich structures is emerging as an important strategy for structural modification and optimization,which can improve the bioactivity of drugs.Herein,we report a visible-light-...Imposing conformational constraints on sp3-rich structures is emerging as an important strategy for structural modification and optimization,which can improve the bioactivity of drugs.Herein,we report a visible-light-induced photosensitized[2+2]homo-cycloaddition and cross-cycloaddition of cyclopropenes to synthesize tricyclo[3.1.0.0^(2,4)]hexanes as rigidified 3,3,6,6-tetrasubstituted cyclohexanes.Trifluoroacetylsilanes,previously known as trifluoromethyl siloxycarbene precursors,were used as photocatalysts for the first time.The mechanism study supports that the aggregation of cyclopropenes is important to promote their sensitization by trifluoroacetylsilanes through energy transfer.展开更多
Herein we report the first[4+1]cyclization-aromatization reaction of acylsilanes andα,β-unsaturated ketones.The unprecedented visible-light-induced reaction proceeded through mild conditions without addition of any ...Herein we report the first[4+1]cyclization-aromatization reaction of acylsilanes andα,β-unsaturated ketones.The unprecedented visible-light-induced reaction proceeded through mild conditions without addition of any catalyst or additive,affording a variety of furans with broad substrate scope and good functional-group tolerance.The synthetic utility of the method was demonstrated by various downstream transformations of the otherwise difficult-to-access sulfone-containing silyl furans.The mechanism study reveals that 1,4-diketones are not likely to be the intermediates of the reaction.展开更多
Visible light promoted C-O bond formation reaction through O-H insertion of acylsilanes with oximes has been developed.The reaction occurred under mild reaction conditions(sole blue LED irradiation in the absence of a...Visible light promoted C-O bond formation reaction through O-H insertion of acylsilanes with oximes has been developed.The reaction occurred under mild reaction conditions(sole blue LED irradiation in the absence of any catalysts or additives)with a short reaction time and afforded the corresponding oxime ethers in moderate to good yields.展开更多
Thioamide was straightforwardly constructed via a chemoselective one-pot synthesis,employing acylsilanes in conjunction with diverse amines and elemental sulfur.The driving force of thioamidation stemmed from silane m...Thioamide was straightforwardly constructed via a chemoselective one-pot synthesis,employing acylsilanes in conjunction with diverse amines and elemental sulfur.The driving force of thioamidation stemmed from silane migration,a synergy process of lone pair electron attack from amine and more stable Si-O bond formation,followed by the nucleophilic activation of elemental sulfur via carbanion intermediate.The leaving trend of trimethylsilanolate and nucleophilicity of linear polysulfur facilitated the cleavage of the S-S bond affording thioamide.A variety of sensitive functional groups,including unprotected hydroxyl,carboxyl and difluoride substitution moieties,are well tolerated under the reaction conditions.Site-selective introduction of thioamide was further demonstrated for the biologically active molecule linkage,displaying the advantages compared with the conventional Lawesson's reagent.展开更多
A novel method for synthesizingα-oxygen organoboron compounds has been developed through acylsilane-based carbene insertion reactions into C—B bonds.As coupling partners,readily available organoboron compounds(alken...A novel method for synthesizingα-oxygen organoboron compounds has been developed through acylsilane-based carbene insertion reactions into C—B bonds.As coupling partners,readily available organoboron compounds(alkenyl,allyl,and allenyl B(pin))were employed.Based on the substrates,pure insertion into C—B bonds or insertion followed by a siloxy group rearrangement process(from carbon to boron)would occur,delivering theα-oxygen organoboron compounds with great diversities.Control experiments demonstrated that the electronic effect of the substituents mainly controlled the rearrangement process.Besides,no matter which isomer of substrate(Z or E)was used,the reaction withβ-aryl-substituted alkenyl B(pin)affords both isomers of products(Z and E,separable through column chromatography).Trapping experiments indicated the triplet energy transfer process was involved.展开更多
The catalytic asymmetric synthesis of novel and chiral amino acid derivatives with unconventional chemo-,diastereo-,and enantio-selectivity remains a paramount challenge.Herein we reported a novel protocol for the use...The catalytic asymmetric synthesis of novel and chiral amino acid derivatives with unconventional chemo-,diastereo-,and enantio-selectivity remains a paramount challenge.Herein we reported a novel protocol for the use of highly enantioselective copper-catalyzed cycloaddition ofα,β-unsaturated acylsilanes as a springboard reaction for the facile synthesis of structurally diversified pyrrolidines and complicatedα-amino esters by desilylation.The newly developed process could provide a wide range of synthetically useful acylsilane-substituted pyrrolidines(ASiP)in high yields and excellent diastereo-and enantioselectivities with Cu/(R)-XylBINAP complex as the catalyst.And the downstream desilylation transformation enables to expand the potntial applications of 1,3-dipolar cycloaddition in the construction of structurally unique amino acid derivatives,in which an unprecedented and concerted fluoride anion-promoted C–X(X=H,Si,N,C)bond cleavage occurred to the enantioselective construction of aldehyde-substituted pyrrolidines,linear cinnamaldehyde or alkene-substituted amino esters in high ee values.展开更多
基金supported by the National Natural Science Foundation of China(grant no.22271156)the Fundamental Research Funds for the Central Universities(grant no.30921011206).
文摘Acylsilanes are versatile building blocks widely used in organic transformations.However,the current synthetic approaches require multiple steps,as well as the use of silyl metals or sensitive reagents or copious amounts of transition-metal catalysts,complex ligands,and elevated temperatures.In this study,a novel visible-light-mediated,metal-free approach for generating silyl acyl radical intermediates via the reaction of silyl radicals and CO is reported.By trapping the species with various reagents,a wide range of acylsilanes could be accessed smoothly under mild conditions,with high atom economy.Gramscale synthesis could be easily achieved using continuous-flow reactors,indicating the potential for industrial-scale manufacturing and enhanced process safety.Furthermore,these generated acylsilanes could be employed in synthesizing valuable skeletons such asα-alkoxyorganoboronate esters,cyclopropanes,modified tryptophan-containing oligopeptides,andα-silyl alcohols through simple transformations.We anticipate that this strategy would be universally applicable for constructing diverse acylsilanes and complement current catalysis methodologies.
基金financial support from the National Key R&D Program of China(2022YFA1506100)Fundamental Research Funds for the Central Universities(2042023kf1010,2042023kf0202).
文摘Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material chemistry.In this review,we summarize the investigations on the synthesis of organofluorine compounds with acylsilanes.For the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-difluoroketones.For the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine compounds.In general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.
基金National Key R&D Program of China(No.2022YFA1506100)National Natural Science Foundation of China(Nos.22471201,21901191)+1 种基金Fundamental Research Funds for the Central Universities(No.2042023kf0202)Wuhan University for financial support。
文摘Imposing conformational constraints on sp3-rich structures is emerging as an important strategy for structural modification and optimization,which can improve the bioactivity of drugs.Herein,we report a visible-light-induced photosensitized[2+2]homo-cycloaddition and cross-cycloaddition of cyclopropenes to synthesize tricyclo[3.1.0.0^(2,4)]hexanes as rigidified 3,3,6,6-tetrasubstituted cyclohexanes.Trifluoroacetylsilanes,previously known as trifluoromethyl siloxycarbene precursors,were used as photocatalysts for the first time.The mechanism study supports that the aggregation of cyclopropenes is important to promote their sensitization by trifluoroacetylsilanes through energy transfer.
基金the National Natural Science Foundation of China(grant no.21901191)the Fundamental Research Funds for the Central Universities,and Wuhan University for financial support.
文摘Herein we report the first[4+1]cyclization-aromatization reaction of acylsilanes andα,β-unsaturated ketones.The unprecedented visible-light-induced reaction proceeded through mild conditions without addition of any catalyst or additive,affording a variety of furans with broad substrate scope and good functional-group tolerance.The synthetic utility of the method was demonstrated by various downstream transformations of the otherwise difficult-to-access sulfone-containing silyl furans.The mechanism study reveals that 1,4-diketones are not likely to be the intermediates of the reaction.
基金We are grateful to the National Natural Science Foundation of China(Nos.21971001,22101002,and 21702001)for financial support.
文摘Visible light promoted C-O bond formation reaction through O-H insertion of acylsilanes with oximes has been developed.The reaction occurred under mild reaction conditions(sole blue LED irradiation in the absence of any catalysts or additives)with a short reaction time and afforded the corresponding oxime ethers in moderate to good yields.
基金supported by the National Natural Science Foundation of China(No.22125103)Science and Technology Commission of Shanghai Municipality(No.22JC1401000).
文摘Thioamide was straightforwardly constructed via a chemoselective one-pot synthesis,employing acylsilanes in conjunction with diverse amines and elemental sulfur.The driving force of thioamidation stemmed from silane migration,a synergy process of lone pair electron attack from amine and more stable Si-O bond formation,followed by the nucleophilic activation of elemental sulfur via carbanion intermediate.The leaving trend of trimethylsilanolate and nucleophilicity of linear polysulfur facilitated the cleavage of the S-S bond affording thioamide.A variety of sensitive functional groups,including unprotected hydroxyl,carboxyl and difluoride substitution moieties,are well tolerated under the reaction conditions.Site-selective introduction of thioamide was further demonstrated for the biologically active molecule linkage,displaying the advantages compared with the conventional Lawesson's reagent.
基金supported by the National Natural Science Foundation of China(22101261)the Natural Science Foundation of Henan Province(232300421087,232301420045)the Zhengzhou University of China(2023ZZUJGXM168).
文摘A novel method for synthesizingα-oxygen organoboron compounds has been developed through acylsilane-based carbene insertion reactions into C—B bonds.As coupling partners,readily available organoboron compounds(alkenyl,allyl,and allenyl B(pin))were employed.Based on the substrates,pure insertion into C—B bonds or insertion followed by a siloxy group rearrangement process(from carbon to boron)would occur,delivering theα-oxygen organoboron compounds with great diversities.Control experiments demonstrated that the electronic effect of the substituents mainly controlled the rearrangement process.Besides,no matter which isomer of substrate(Z or E)was used,the reaction withβ-aryl-substituted alkenyl B(pin)affords both isomers of products(Z and E,separable through column chromatography).Trapping experiments indicated the triplet energy transfer process was involved.
基金supported by the National Natural Science Foundation of China(21773051,21702211,21703051)Zhejiang Provincial Natural Science Foundation of China(LZ18B020001,LQ19B040001,LY18B020013)the Hangzhou Science and Technology Bureau of China(20180432B05)。
文摘The catalytic asymmetric synthesis of novel and chiral amino acid derivatives with unconventional chemo-,diastereo-,and enantio-selectivity remains a paramount challenge.Herein we reported a novel protocol for the use of highly enantioselective copper-catalyzed cycloaddition ofα,β-unsaturated acylsilanes as a springboard reaction for the facile synthesis of structurally diversified pyrrolidines and complicatedα-amino esters by desilylation.The newly developed process could provide a wide range of synthetically useful acylsilane-substituted pyrrolidines(ASiP)in high yields and excellent diastereo-and enantioselectivities with Cu/(R)-XylBINAP complex as the catalyst.And the downstream desilylation transformation enables to expand the potntial applications of 1,3-dipolar cycloaddition in the construction of structurally unique amino acid derivatives,in which an unprecedented and concerted fluoride anion-promoted C–X(X=H,Si,N,C)bond cleavage occurred to the enantioselective construction of aldehyde-substituted pyrrolidines,linear cinnamaldehyde or alkene-substituted amino esters in high ee values.
