Rhodium-catalyzed Reactions Of 3-Diazoindolin-2-imines

3-Diazoindolin-2-imines are a new class of diazo compounds,which were developed by our group in 2014.It has been demonstrated that these diazo compounds could be used as metal carbene precursors for a variety of transformations,leading to the syntheses of a serials of indole ring-containing heterocyclic compounds.As a continuation of this work,we investigated the rhodium(?)-catalyzed reactions between 3-diazoindolin-2-imines with thioesters and benzyl alcohols in this thesis,the results are summarized below.(1)We have demonstrated that 3-diazoindolin-2-imines reacted with thioesters under Rh(II)catalysis to furnish 2-amino-3-(arylthio)indoIes.If cyclic thioester was used as the sulfenylating agents,7,8-dihydrobenzo[7,8][1,4]thiazocino[3,2-b]indol-6(5H)-ones were obtained.The Rh-catalyzed process involved the generation of Rh-carbene complex intermediate,the C-S bond coupling,and 1,4-acyl shift.This reaction could be carried out easily with available reactants and varying group tolerance.Furthermore,the sulfanyl moiety of the synthesized 2-amino-3-(arylthio)indoles could be easily oxidized by mCPBA to give the corresponding 2-amino-3-(arylsulphonyl)indoles,and the N-sulfonyl group could be successfully removed by reduction with SmI2.(2)We have developed a new method for the synthesis of 3,3-dihydroxyindoles from 3-diazoindolin-2-imines and phenylmethanols using Rh(II)catalysts.If 1,2-phenylenedimethanol was used as the alcohol component,spiro[benzo[1,3]dioxepine-3,3'-indoline]were directly generated.