Chemoselectivity in Dirhodium(II) Catalyzed Reactions of Diazoacetoacetates Prepared from α,β-Unsaturated Ketones

α-Diazo β-keto esters from zinc triflate catalyzed Mukaiyama-Michael reactions between α,β unsaturated ketones and α silyloxyvinyldiazoacetates are valuable synthons for the synthesis of compounds that can be accessed through catalytic diazo decomposition. Two sets of examples involving C-H insertion and aromatic substitution demonstrate the versatility of this methodology.