Homologation of Alkyl Acetates or Acetals by Formal Insertion ofDiazo Esters into a Carbon-Carbon Bond

摘要

Homologation of organic compounds by selective one-carbon-insertion into carboncarbonσ-bonds to construct new two C-C bonds simultaneously is a powerful tool in organicsynthesis.Diazo compounds have been widely explored as a one-carbon-source undertransition metal catalysis.Formal insertions of diazo compounds into a C-C bond of cyclicstructures are usually reported.1 In those reports,the release of ring strain provides a crucialthermodynamic driving force.However,the selective one-carbon insertion into unstrainedacyclic C-C σ-bonds is still a challenge.In addition,most related C-C insertion reactions basedon carbonyl group systems,2 which obviously limits the development of this field.Hence,indepthresearches toward other functional groups like alkoxy and acetoxy groups,are necessary.Herein we report homologation of alkyl acetates or acetals by formal insertion of diazo estersinto a carbon-carbon bond.