Relay Rh(ii)/Pd(0) dual catalysis: synthesis of α-quaternary ß-keto-esters via a [1,2]-sigmatropic rearrangement/allylic alkylation cascade of α-diazo tertiary alcohols.

A relay Rh(ii)/Pd(0) dual catalysis that enables domino [1,2]-sigmatropic rearrangement/allylic alkylation of α-diazo tertiary alcohols is described. This transformation represents a highly efficient method for the one-pot synthesis of α-quaternary ß-keto-esters under mild conditions, in which two separate C-C σ-bonds at the carbenic center were formed in a straightforward manner.