Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and electrophiles.However,the inclusion of alkylarenes instead of active carbon pronucleophil...Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and electrophiles.However,the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic deprotonation.In this study,we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic C–H bonds to cyclic N-sulfonyl ketamines throughπ-coordination.This strategy enables the synthesis of a diverse range of N-sulfonyl amines,and subsequent diversification of the addition products showcases the synthetic potential of this protocol.展开更多
Chiral dihydrobenzofuran is a valuable synthetic fragment in both medicinal and organic chemistry.Efficient rhodium(Ⅲ)-catalyzed chemoselective and enantioselective C-H functionalization/[3+2]annulation of N-phenoxya...Chiral dihydrobenzofuran is a valuable synthetic fragment in both medicinal and organic chemistry.Efficient rhodium(Ⅲ)-catalyzed chemoselective and enantioselective C-H functionalization/[3+2]annulation of N-phenoxyacetamides with 1,3-dienes is reported.In the presence of 5 mol%Cp Rh complex,various chiral dihydrobenzofurans were synthesized in up to 79%yield and 98%ee.This reaction proceeds under mild conditions with excellent functional group compatibility.展开更多
Electrochemistry-enabled rhodium-catalyzed C–H amination and amination cyclization of arene assisted by a weakly coordinating amide have been reported. Additionally, aryl amines and dihydroquinazolinones could be obt...Electrochemistry-enabled rhodium-catalyzed C–H amination and amination cyclization of arene assisted by a weakly coordinating amide have been reported. Additionally, aryl amines and dihydroquinazolinones could be obtained selectively by controlling the electric current. Mechanistic studies suggested that the amination reaction likely involves an electrochemical oxidation-induced reductive elimination of a high valent rhodium intermediate, which led to the amination reaction even proceeding smoothly at room temperature.展开更多
Different from the established trans-endo-selective cyclization of alkyne-tethered electrophiles that involve an E/Z isomerization process,herein,the authors present a novel strategy to allow trans-exo-selective aryla...Different from the established trans-endo-selective cyclization of alkyne-tethered electrophiles that involve an E/Z isomerization process,herein,the authors present a novel strategy to allow trans-exo-selective arylative cyclization of 1,6-enynes.Through initiation of rhodium(III)-catalyzed C-H activation,a diverse range of N-heterocyclic directing groups,including pyridine,pyrazole,imidazo[1,2-a]pyridine,benzoxazole,benzothiazole,and purine,was feasible for the cascade transformation,exhibiting high efficiency(up to 92%yield),broad substrate scope,and excellent functional group compatibility.Moreover,the modification of natural products and pharmaceutical compounds was also demonstrated to showcase its synthetic utility.Based on density functional theory(DFT)calculations,a key three-membered ring intermediate through the insertion relay,rather than the direct E/Z isomerization of alkenyl rhodium species,controlled the stereochemical outcome for this trans-exo-selective cyclization.The subsequent ring-opening protonation of the more favored rotamer led to exclusive trans-exo-selectivity.展开更多
Here, a rhodium(Ⅲ)-catalyzed benzo[c]azepine-1,3(2 H)-dione synthesis via tandem C-H alkylation and intramolecular amination of N-methoxylbenzamide with 3-bromo-3,3-difluoropropene as the alkylation agent is reported...Here, a rhodium(Ⅲ)-catalyzed benzo[c]azepine-1,3(2 H)-dione synthesis via tandem C-H alkylation and intramolecular amination of N-methoxylbenzamide with 3-bromo-3,3-difluoropropene as the alkylation agent is reported. The substituted benzamides and protected indoles are all tolerated, yielding the corresponding products in moderate to good yields. Further study revealed those bioactive compounds such as piperic acid and a key precursor of Roflumilast all perform well, highlighting the synthetic utility of this method.展开更多
The synergistic use of transition metal catalysis and electrochemistry is an attractive strategy for oxidative site-selective C–H functionalization since the use of stoichiometric chemical oxidants can be avoided and...The synergistic use of transition metal catalysis and electrochemistry is an attractive strategy for oxidative site-selective C–H functionalization since the use of stoichiometric chemical oxidants can be avoided and novel reactivity can be achieved.However,metalcatalyzed electrochemical C–H functionalization is mainly limited to arene C(sp^(2))–Hfunctionalization,and enantioselective C–H functionalization is uncommon and remains challenging.展开更多
The Cp;Rh(Ⅲ)-catalyzed asymmetric cascade C-H coupling/intramolecular cyclization of azomethine imines with propargyl carbonates has been developed, affording a variety of chiral tetracyclic indenopyrazolopyrazolone ...The Cp;Rh(Ⅲ)-catalyzed asymmetric cascade C-H coupling/intramolecular cyclization of azomethine imines with propargyl carbonates has been developed, affording a variety of chiral tetracyclic indenopyrazolopyrazolone frameworks with good substrate/functional group tolerance and enantioselectivity(up to 97:3 er). Combined experimental studies and DFT calculations revealed the Rh(Ⅲ)-catalyzed stepwise annulation process and clarified the synergy coordination mode of dual directing groups in tuning the selectivity.展开更多
Comprehensive Summary Herein,we have developed a strategy of Rh(III)-catalyzed C—H activation of N-nitrosoanilines and iodonium ylides to construct novel tetralydrocarbzol-4-one scaffolds,which provided valuable temp...Comprehensive Summary Herein,we have developed a strategy of Rh(III)-catalyzed C—H activation of N-nitrosoanilines and iodonium ylides to construct novel tetralydrocarbzol-4-one scaffolds,which provided valuable templates for sequential C—H functionalization such as alkylation,alkenylation,amidation and(hetero)arylation at C^(5)-position of tetralydrocarbzol-4-one with different coupling partners.Gram-scale synthesis and further transformations of tetralydrocarbzol-4-one derivatives to Ondansetron and its analogues demonstrated the utility of this protocol,which enabled the concise and diverse construction of biologically active molecules.展开更多
Conjugated polyene motifs are ubiquitous in various natural products and functional molecules;however,their synthesis is very challenging because of the required lengthy and time-consuming processes.We herein report a...Conjugated polyene motifs are ubiquitous in various natural products and functional molecules;however,their synthesis is very challenging because of the required lengthy and time-consuming processes.We herein report an efficient approach for the synthesis of(E,E)-trienes via cationic rhodium catalysis using acetylene and simple alkenes bearing diverse directing groups as the starting materials.The reaction featured high step economy,excellent functional group compatibility,and exclusive stereoselectivity.Various directing groups such as carbonyl,sulfone,phosphate,hydroxyl,and amino were compatible.Furthermore,the triene products allowed versatile elaborations,providing rapid and convenient access to several important bioactive molecules,including vitamin A,(+)-roxaticin,and other complex polyenes.Mechanistic experiments showed that the directing group on the alkene played a crucial role in the reaction.展开更多
Disclosed herein is a novel Rh/Ag co-catalyzed S=NH directed C–H activation and C–H/N–H bond functionalization protocol of free NH-sulfoximines with hypervalent iodonium ylides.With the aid of AgOTf,these C–H func...Disclosed herein is a novel Rh/Ag co-catalyzed S=NH directed C–H activation and C–H/N–H bond functionalization protocol of free NH-sulfoximines with hypervalent iodonium ylides.With the aid of AgOTf,these C–H functionalization/cyclization sequences could be achieved at room temperature conditions.The reaction employed EtOH as a“green”solvent and low catalyst loading was required under an oxygen/water-insensitive condition.Under this mild protocol,a wide range of polyheterocyclic sulfoximines bearing fused saturated carbo(hetero)cycles are readily prepared,even toward a complex pharmaceutical Folliculin analog.展开更多
By developing gem-difluoromethylene allenes as viable partners,regiocontrolled Rh(Ⅲ)-catalyzed redoxneutral C-C coupling/C-N cyclization has been realized to build the pyridin-2(1H)-one motifs with the embedment of a...By developing gem-difluoromethylene allenes as viable partners,regiocontrolled Rh(Ⅲ)-catalyzed redoxneutral C-C coupling/C-N cyclization has been realized to build the pyridin-2(1H)-one motifs with the embedment of a Z-configured monofluoroalkene functionality,in which either(hetero)aromatic or vinylic amides were found to be compatible.Integrated experimental and computational mechanistic studies revealed that a tandem regioselective allene 1,2-insertion/β-H elimination/hydrogen transfer/oxidative addition/cyclization/cis-β-F elimination involving an unconventional Rh(Ⅲ)-Rh(I)-Rh(Ⅲ)catalytic cycle accounts for the established transformation.Through further FMO analysis and IGMH maps,a non-covalent weak interaction network between the gem-difluoromethylene part and the OPiv moiety was rationally defined for the unconventional and specific regioselectivity control.展开更多
Rhodium(III)catalysis has set the stage for a plethora of oxidative C–H functionalizations over the last decade,which have predominantly employed stoichiometric amounts of toxic and expensive metal oxidants,such as s...Rhodium(III)catalysis has set the stage for a plethora of oxidative C–H functionalizations over the last decade,which have predominantly employed stoichiometric amounts of toxic and expensive metal oxidants,such as silver(I)salts.In the meantime,electrosynthesis has emerged as an increasingly viable alternative for expensive and toxic oxidants.Recently,significant momentum has been achieved with the merger of electrocatalysis with organometallic C–H activation.However,user-friendly and robust rhodaelectro-catalysis has until very recently proven elusive for oxidative C–H activations.This minireview highlights the current knowledge and recent advances of electrooxidation in rhodium-catalyzed C–H or C–C activations,with a topical focus on contributions from the Ackermann group through July 2020.展开更多
The[2,3]-and[1,2]-sigmatropic rearrangement reactions between pyridotriazoles and sulfides catalyzed by rhodium(II)were investigated.The utilization of pyridotriazoles as the carbene precursors in this kind of reactio...The[2,3]-and[1,2]-sigmatropic rearrangement reactions between pyridotriazoles and sulfides catalyzed by rhodium(II)were investigated.The utilization of pyridotriazoles as the carbene precursors in this kind of reaction efficiently constructed the C(sp3)-S and C(sp3)-Se bond with broad substrate scope and great functional group tolerance.展开更多
基金the National Natural Science Foundation of China(Nos.22271235,22071198)the“Pioneer”and“Leading Goose”R&D Program of Zhejiang(No.2022SDXHDX0006)the Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang(No.2020R01004)for research support。
文摘Mannich-type reactions are a widely used method for the synthesis of amines due to the readily availability of nucleophiles and electrophiles.However,the inclusion of alkylarenes instead of active carbon pronucleophiles such as aldehydes and ketones in these addition reactions has been a challenge due to the inherent difficulty of benzylic deprotonation.In this study,we present a novel approach for the construction of N-sulfonyl amines via rhodium-catalyzed addition of unbiased benzylic C–H bonds to cyclic N-sulfonyl ketamines throughπ-coordination.This strategy enables the synthesis of a diverse range of N-sulfonyl amines,and subsequent diversification of the addition products showcases the synthetic potential of this protocol.
基金supported by the National Key Research and Development Program of China(2021YFA1500100)the National Natural Science Foundation of China(21821002,92256302,22071260)the Science and Technology Commission of Shanghai Municipality(21520780100)。
文摘Chiral dihydrobenzofuran is a valuable synthetic fragment in both medicinal and organic chemistry.Efficient rhodium(Ⅲ)-catalyzed chemoselective and enantioselective C-H functionalization/[3+2]annulation of N-phenoxyacetamides with 1,3-dienes is reported.In the presence of 5 mol%Cp Rh complex,various chiral dihydrobenzofurans were synthesized in up to 79%yield and 98%ee.This reaction proceeds under mild conditions with excellent functional group compatibility.
基金supported by the National Key Research and Development Program of China (2021YFA1500100)the National Natural Science Foundation of China (21821002, 21772222, 91956112)+1 种基金the Science and Technology Commission of Shanghai Municipality (S&TCSM) of Shanghai (18JC1415600, 20JC1417100)Bayer AG (Germany)。
文摘Electrochemistry-enabled rhodium-catalyzed C–H amination and amination cyclization of arene assisted by a weakly coordinating amide have been reported. Additionally, aryl amines and dihydroquinazolinones could be obtained selectively by controlling the electric current. Mechanistic studies suggested that the amination reaction likely involves an electrochemical oxidation-induced reductive elimination of a high valent rhodium intermediate, which led to the amination reaction even proceeding smoothly at room temperature.
基金Financial support was generously provided by the National Natural Science Foundation of China(nos.21871184,21871284,21702182,and 21873081),the Shanghai Municipal Education Commission(no.2019-01-07-00-10-E00072),the Science and Technology Commission of Shanghai Municipality(no.18401933500),the Strategic Priority Research Program of the Chinese Academy of Sciences(no.XDB 20020100),the Key Research Program of Frontier Science(no.QYZDYSSW-SLH026),the Fundamental Research Funds for the Central Universities(no.2019QNA3009),and the China Postdoctoral Science Foundation(no.2018M640546).Calculations were performed on the high-performance computing system at the Department of Chemistry,Zhejiang University.The authors thank Jie Sun(Shanghai Institute of Organic Chemistry)for X-ray crystallographic analysis.
文摘Different from the established trans-endo-selective cyclization of alkyne-tethered electrophiles that involve an E/Z isomerization process,herein,the authors present a novel strategy to allow trans-exo-selective arylative cyclization of 1,6-enynes.Through initiation of rhodium(III)-catalyzed C-H activation,a diverse range of N-heterocyclic directing groups,including pyridine,pyrazole,imidazo[1,2-a]pyridine,benzoxazole,benzothiazole,and purine,was feasible for the cascade transformation,exhibiting high efficiency(up to 92%yield),broad substrate scope,and excellent functional group compatibility.Moreover,the modification of natural products and pharmaceutical compounds was also demonstrated to showcase its synthetic utility.Based on density functional theory(DFT)calculations,a key three-membered ring intermediate through the insertion relay,rather than the direct E/Z isomerization of alkenyl rhodium species,controlled the stereochemical outcome for this trans-exo-selective cyclization.The subsequent ring-opening protonation of the more favored rotamer led to exclusive trans-exo-selectivity.
基金supported by the Natural Science Foundation of China (No.21772139)the Jiangsu Province Natural Science Found for Distinguished Young Scholars (No.BK20180041)+1 种基金the PAPD Projectsupported by the Open Research Fund of the School of Chemistry and Chemical Engineering,Henan Normal University。
文摘Here, a rhodium(Ⅲ)-catalyzed benzo[c]azepine-1,3(2 H)-dione synthesis via tandem C-H alkylation and intramolecular amination of N-methoxylbenzamide with 3-bromo-3,3-difluoropropene as the alkylation agent is reported. The substituted benzamides and protected indoles are all tolerated, yielding the corresponding products in moderate to good yields. Further study revealed those bioactive compounds such as piperic acid and a key precursor of Roflumilast all perform well, highlighting the synthetic utility of this method.
基金grant fromNSFC(nos.21821002,21772222,and 91956112),CAS(no.XDB20000000)Science and Technology Commission of Shanghai Municipality(nos.18JC1415600 and 20JC1417100).
文摘The synergistic use of transition metal catalysis and electrochemistry is an attractive strategy for oxidative site-selective C–H functionalization since the use of stoichiometric chemical oxidants can be avoided and novel reactivity can be achieved.However,metalcatalyzed electrochemical C–H functionalization is mainly limited to arene C(sp^(2))–Hfunctionalization,and enantioselective C–H functionalization is uncommon and remains challenging.
基金National Natural Science Foundation of China (NSFC,Nos.21877020,22007020)Guangdong Natural Science Funds for Distinguished Young Scholar (No.2017A030306031)Natural Science Foundation of Guangdong Province (No.2019A1515010935) for financial support on this study。
文摘The Cp;Rh(Ⅲ)-catalyzed asymmetric cascade C-H coupling/intramolecular cyclization of azomethine imines with propargyl carbonates has been developed, affording a variety of chiral tetracyclic indenopyrazolopyrazolone frameworks with good substrate/functional group tolerance and enantioselectivity(up to 97:3 er). Combined experimental studies and DFT calculations revealed the Rh(Ⅲ)-catalyzed stepwise annulation process and clarified the synergy coordination mode of dual directing groups in tuning the selectivity.
基金the National Natural Science Foundation of China(Nos.82130105,82103969 and 82273766)SA-SIBS Scholarship Program,the Youth Innovation Promotion Association CAS(2020282)grant from Lingang Laboratory(LG202103-02-06).
文摘Comprehensive Summary Herein,we have developed a strategy of Rh(III)-catalyzed C—H activation of N-nitrosoanilines and iodonium ylides to construct novel tetralydrocarbzol-4-one scaffolds,which provided valuable templates for sequential C—H functionalization such as alkylation,alkenylation,amidation and(hetero)arylation at C^(5)-position of tetralydrocarbzol-4-one with different coupling partners.Gram-scale synthesis and further transformations of tetralydrocarbzol-4-one derivatives to Ondansetron and its analogues demonstrated the utility of this protocol,which enabled the concise and diverse construction of biologically active molecules.
基金the NSFC(grant nos.21871096,22071062,22271096),and the Fundamental Research Funds for the Central Universities,SCUT.
文摘Conjugated polyene motifs are ubiquitous in various natural products and functional molecules;however,their synthesis is very challenging because of the required lengthy and time-consuming processes.We herein report an efficient approach for the synthesis of(E,E)-trienes via cationic rhodium catalysis using acetylene and simple alkenes bearing diverse directing groups as the starting materials.The reaction featured high step economy,excellent functional group compatibility,and exclusive stereoselectivity.Various directing groups such as carbonyl,sulfone,phosphate,hydroxyl,and amino were compatible.Furthermore,the triene products allowed versatile elaborations,providing rapid and convenient access to several important bioactive molecules,including vitamin A,(+)-roxaticin,and other complex polyenes.Mechanistic experiments showed that the directing group on the alkene played a crucial role in the reaction.
基金the National Natural Science Foundation of China(No.21961015)the Natural Science Foundation of Jiangxi Province(No.20202ACBL203005)for their financial support.
文摘Disclosed herein is a novel Rh/Ag co-catalyzed S=NH directed C–H activation and C–H/N–H bond functionalization protocol of free NH-sulfoximines with hypervalent iodonium ylides.With the aid of AgOTf,these C–H functionalization/cyclization sequences could be achieved at room temperature conditions.The reaction employed EtOH as a“green”solvent and low catalyst loading was required under an oxygen/water-insensitive condition.Under this mild protocol,a wide range of polyheterocyclic sulfoximines bearing fused saturated carbo(hetero)cycles are readily prepared,even toward a complex pharmaceutical Folliculin analog.
基金the National Natural Science Foundation of China(NSFC,Nos.21877020,22007020)Natural Science Foundation of Guangdong Province(No.2019A1515010935)Science and Technology Program of Guangzhou(No.202102020615)for financial support on this study。
文摘By developing gem-difluoromethylene allenes as viable partners,regiocontrolled Rh(Ⅲ)-catalyzed redoxneutral C-C coupling/C-N cyclization has been realized to build the pyridin-2(1H)-one motifs with the embedment of a Z-configured monofluoroalkene functionality,in which either(hetero)aromatic or vinylic amides were found to be compatible.Integrated experimental and computational mechanistic studies revealed that a tandem regioselective allene 1,2-insertion/β-H elimination/hydrogen transfer/oxidative addition/cyclization/cis-β-F elimination involving an unconventional Rh(Ⅲ)-Rh(I)-Rh(Ⅲ)catalytic cycle accounts for the established transformation.Through further FMO analysis and IGMH maps,a non-covalent weak interaction network between the gem-difluoromethylene part and the OPiv moiety was rationally defined for the unconventional and specific regioselectivity control.
基金support by the Deutsche Forschungsgemeinschaft(German Research Foundation)(Gottfried-Wilhelm-Leibniz award to L.A.)and the China Scholarship Council(fellowship to C.Z.)is gratefully acknowledged.
文摘Rhodium(III)catalysis has set the stage for a plethora of oxidative C–H functionalizations over the last decade,which have predominantly employed stoichiometric amounts of toxic and expensive metal oxidants,such as silver(I)salts.In the meantime,electrosynthesis has emerged as an increasingly viable alternative for expensive and toxic oxidants.Recently,significant momentum has been achieved with the merger of electrocatalysis with organometallic C–H activation.However,user-friendly and robust rhodaelectro-catalysis has until very recently proven elusive for oxidative C–H activations.This minireview highlights the current knowledge and recent advances of electrooxidation in rhodium-catalyzed C–H or C–C activations,with a topical focus on contributions from the Ackermann group through July 2020.
基金Sichuan Science and Technology Program(No.2020YJ0221).
文摘The[2,3]-and[1,2]-sigmatropic rearrangement reactions between pyridotriazoles and sulfides catalyzed by rhodium(II)were investigated.The utilization of pyridotriazoles as the carbene precursors in this kind of reaction efficiently constructed the C(sp3)-S and C(sp3)-Se bond with broad substrate scope and great functional group tolerance.