Synthesis of Complex Allylic Esters via C-H Oxidation vs C-C Bond Formation

A highly general, predictably selective C H oxidation method for the direct, catalytic synthesis of complex allylic esters is introduced. This Pd(II)/sulfoxide-catalyzed method allows a wide range of complex aryl and alkyl carboxylic acids to couple directly with terminal olefins to furnish (E)-allylic esters in synthetically useful yields and selectivities (1 6 examples, EIZ L- 10:1) and without the use of stoichiometric coupling reagents or unstable intermediates. Strategic advantages of constructing allylic esters via C H oxidation vs C C bond-forming methods are evaluated and discussed in four case studies.