A rhodium-catalyzed denitrogenative carbonylation of 1,2,3-thiadiazole with alkynes to construct(benzo)thiochromenones is developed.Both terminal and internal alkynes were compatible in this[3+2+1]cycloaddition,afford...A rhodium-catalyzed denitrogenative carbonylation of 1,2,3-thiadiazole with alkynes to construct(benzo)thiochromenones is developed.Both terminal and internal alkynes were compatible in this[3+2+1]cycloaddition,affording a broad range of poly-substituted thiochromenones.Unsymmetrical alkyne substrates exhibited good regioselectivity.展开更多
Catalytic C–H activation-initiated annulation reactions have emerged as a versatile strategy for the efficient construction of diverse ring structural units and complex cyclic molecules in synthetic chemistry.Herein,...Catalytic C–H activation-initiated annulation reactions have emerged as a versatile strategy for the efficient construction of diverse ring structural units and complex cyclic molecules in synthetic chemistry.Herein,we describe a new Rh(Ⅲ)-catalyzed C–H activation-initiated transdiannulation reaction of N,Ndimethyl enaminones with gem-difluorocyclopropenes in the presence of H_(2)O,enabling a facile and oxygen transfer access to ring-fluorinated tricyclicγ-lactones with a 6-5 ring-junction tetrasubstituted stereocenter.This approach features bond-forming/annulation efficiency,good functional group tolerance and complete regioselectivity,which may include a complex process consisting of Rh(Ⅲ)-catalyzed C(sp2)–H activation,cyclic alkene insertion,defluorinated ring-opening of gem-difluorocyclopropane,intramolecular oxygen transfer,intramolecular cyclization and oxidative hydration.展开更多
基金We acknowledge the National Key R&D Program of China(No.2021YFA1501700)the NSFC(Nos.22131002,22161142019,81821004)the Tencent Foundation for financial support.
文摘A rhodium-catalyzed denitrogenative carbonylation of 1,2,3-thiadiazole with alkynes to construct(benzo)thiochromenones is developed.Both terminal and internal alkynes were compatible in this[3+2+1]cycloaddition,affording a broad range of poly-substituted thiochromenones.Unsymmetrical alkyne substrates exhibited good regioselectivity.
基金financial support from the schoollevel research projects of Yancheng Institute of Technology(No.xjr2020044)the National Natural Science Foundation of China(Nos.22101152,22271123 and 21971090)。
文摘Catalytic C–H activation-initiated annulation reactions have emerged as a versatile strategy for the efficient construction of diverse ring structural units and complex cyclic molecules in synthetic chemistry.Herein,we describe a new Rh(Ⅲ)-catalyzed C–H activation-initiated transdiannulation reaction of N,Ndimethyl enaminones with gem-difluorocyclopropenes in the presence of H_(2)O,enabling a facile and oxygen transfer access to ring-fluorinated tricyclicγ-lactones with a 6-5 ring-junction tetrasubstituted stereocenter.This approach features bond-forming/annulation efficiency,good functional group tolerance and complete regioselectivity,which may include a complex process consisting of Rh(Ⅲ)-catalyzed C(sp2)–H activation,cyclic alkene insertion,defluorinated ring-opening of gem-difluorocyclopropane,intramolecular oxygen transfer,intramolecular cyclization and oxidative hydration.
