The chemistry of alkoxy radicals was extensively explored during the period of 1960s to 1990s,but it has remained dormant for the past few decades.Recently,alkoxy radicals attract the attentions again,because new meth...The chemistry of alkoxy radicals was extensively explored during the period of 1960s to 1990s,but it has remained dormant for the past few decades.Recently,alkoxy radicals attract the attentions again,because new methods for generating alkoxy radical species have emerged.These newly developed methods are mainly based on the photolysis by visible light under mild conditions,thus allowing for new transformations of the carbon-centered radical species that are generated from theβ-scission or hydrogen abstraction of the alkoxy radicals.展开更多
Furans bearing alkynyl substituents are highly useful in organic synthesis.However,the methodologies to access these important furan derivatives are rather limited.We herein report an efficient synthesis of alkynylate...Furans bearing alkynyl substituents are highly useful in organic synthesis.However,the methodologies to access these important furan derivatives are rather limited.We herein report an efficient synthesis of alkynylated furan derivatives based on Pd-catalyzed oxidative cross-coupling reaction between allenyl ketones and terminal alkynes.This novel synthesis of alkynylated furans with wide substrate scope is operationally simple and tolerates various functional groups.Mechanistically,the formation of the palladium carbene through cycloisomerization and the subsequent alkynyl migratory insertion are proposed as the key steps in the transformation.The reaction reported in this paper further demonstrates the generality of the carbene-based cross coupling.展开更多
Comprehensive Summary The direct use of non-prefunctionalized arene and alkane as the starting materials to construct Caryl−Calkyl bond is an unfulfilled target and approaches to this challenge rarely surface in metho...Comprehensive Summary The direct use of non-prefunctionalized arene and alkane as the starting materials to construct Caryl−Calkyl bond is an unfulfilled target and approaches to this challenge rarely surface in methodology studies.Current methods for thermocatalytic arene-alkane couplings(AAC)occur with specific substrates and/or inconvenient reagents.Herein,we report a one-pot relay bicatalysis system for AAC involving(pincer)Ir-catalyzed alkane transfer dehydrogenation and Fe(OTf)3-catalyzed olefin hydroarylation.This system exhibits broad scope and is particularly effective for alkylation of arenes with arylalkanes to form 1,1-diarylalkanes with high chemo-and regioselectivity,making it potentially useful for late-stage alkylation of complex molecules.Experimental mechanistic data provide a view into the factors controlling the regioselectivity.Finally,the strategy of dehydrogenation-enabled arene-alkane couplings has been successfully extended to a tandem catalysis by using a heterogeneous olefin hydroarylation catalyst.展开更多
What is the most favorite and original chemistry developed in your research group?Sidearm strategy for the design and modification of organometallic catalysts.How do you get into this specific field? Could you please ...What is the most favorite and original chemistry developed in your research group?Sidearm strategy for the design and modification of organometallic catalysts.How do you get into this specific field? Could you please share some experiences with our readers?Initailly, intrigued by the beauty of C3-symmetry, we try to develop C3-sym-metric trisoxazolines. However, we met a big problem to access it.展开更多
A highly efficient asymmetric cyclopropanation of trisubstituted olefins with methyl diazoacetate has been developed in terms of an elaborate modified chiral bisoxazoline/copper complex as a catalyst. A broad scope of...A highly efficient asymmetric cyclopropanation of trisubstituted olefins with methyl diazoacetate has been developed in terms of an elaborate modified chiral bisoxazoline/copper complex as a catalyst. A broad scope of substrates is compatible with this catalyst system, including various trisubstituted olefins bearing different aryl-, fused aryl-and alkyl-substituents, providing an easy access to optically active 1,1-dimethyl cyclopropanes in good yields with excellent diastereo-and enantio-selectivity.展开更多
基金The project is supported by NSFC(91956104),BNLMS,and Laboratory for Synthetic Chemistry and Chemical Biology of Health@InnoHK of ITC,HKSAR.
文摘The chemistry of alkoxy radicals was extensively explored during the period of 1960s to 1990s,but it has remained dormant for the past few decades.Recently,alkoxy radicals attract the attentions again,because new methods for generating alkoxy radical species have emerged.These newly developed methods are mainly based on the photolysis by visible light under mild conditions,thus allowing for new transformations of the carbon-centered radical species that are generated from theβ-scission or hydrogen abstraction of the alkoxy radicals.
基金supported by NSFC(22371008),BNLMSLaboratory for Synthetic Chemistry and Chemical Biology of Health@InnoHK of ITC,HKSAR.
文摘Furans bearing alkynyl substituents are highly useful in organic synthesis.However,the methodologies to access these important furan derivatives are rather limited.We herein report an efficient synthesis of alkynylated furan derivatives based on Pd-catalyzed oxidative cross-coupling reaction between allenyl ketones and terminal alkynes.This novel synthesis of alkynylated furans with wide substrate scope is operationally simple and tolerates various functional groups.Mechanistically,the formation of the palladium carbene through cycloisomerization and the subsequent alkynyl migratory insertion are proposed as the key steps in the transformation.The reaction reported in this paper further demonstrates the generality of the carbene-based cross coupling.
基金the National Key R&D Program of China(2021YFA1501700)the National Natural Science Foundation of China(21825109,21821002,22072178,22293013).
文摘Comprehensive Summary The direct use of non-prefunctionalized arene and alkane as the starting materials to construct Caryl−Calkyl bond is an unfulfilled target and approaches to this challenge rarely surface in methodology studies.Current methods for thermocatalytic arene-alkane couplings(AAC)occur with specific substrates and/or inconvenient reagents.Herein,we report a one-pot relay bicatalysis system for AAC involving(pincer)Ir-catalyzed alkane transfer dehydrogenation and Fe(OTf)3-catalyzed olefin hydroarylation.This system exhibits broad scope and is particularly effective for alkylation of arenes with arylalkanes to form 1,1-diarylalkanes with high chemo-and regioselectivity,making it potentially useful for late-stage alkylation of complex molecules.Experimental mechanistic data provide a view into the factors controlling the regioselectivity.Finally,the strategy of dehydrogenation-enabled arene-alkane couplings has been successfully extended to a tandem catalysis by using a heterogeneous olefin hydroarylation catalyst.
基金We thank for the financial support from the National Natural Science Foundation of China （Nos. 21421091 and 21432011）, the National Basic Research Program of China （973 Program） （2015CB856600）, the Natural Science Foundation of Shanghai （17ZR1436900）, the Strategic Priority Research Program of the Chinese Academy of Sciences （Grant No. XDB20000000） and the Youth Innovation Promotion Association CAS （2017301）. We thank Dr. Xue-Bing Leng for X-ray crystal analysis
基金the financial support from the National Natural Science Foundation of China (Nos.21432011and 21772224)the Key Research Program of Frontier Sciences,the CAS (No. QYZDY-SSW-SLH016)+3 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences (No.XDB20000000)the Youth Innovation Promotion Association,CAS (No.2017301)the Shanghai Science and Technology Committee (No.17JC1401200)the Natural Science Foundation of Shanghai (No. 17ZR1436900).
文摘What is the most favorite and original chemistry developed in your research group?Sidearm strategy for the design and modification of organometallic catalysts.How do you get into this specific field? Could you please share some experiences with our readers?Initailly, intrigued by the beauty of C3-symmetry, we try to develop C3-sym-metric trisoxazolines. However, we met a big problem to access it.
基金supported by the National Natural Science Foundation of China(21432011,21772224)Key Research Program of Frontier Sciences of Chinese Academy of Sciences(QYZDY-SSWSLH016)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB20000000)the Youth Innovation Promotion Association CAS(2017301)the National Basic Research Program of China(2015CB856600)
文摘A highly efficient asymmetric cyclopropanation of trisubstituted olefins with methyl diazoacetate has been developed in terms of an elaborate modified chiral bisoxazoline/copper complex as a catalyst. A broad scope of substrates is compatible with this catalyst system, including various trisubstituted olefins bearing different aryl-, fused aryl-and alkyl-substituents, providing an easy access to optically active 1,1-dimethyl cyclopropanes in good yields with excellent diastereo-and enantio-selectivity.
