Aldehyde Selective Wacker Oxidations of Phthalimide Protected Allylic Amines: A New Catalytic Route to β3-Amino Acids

A new method for the synthesis of β3-amino acids is presented. Phthalimide protected allylic amines are oxidized under Wacker conditions selectively to aldehydes using PdCl2 and CuCl or Pd(MeCN)2Cl(NO2) and CuCl2 as complementary catalyst systems. The aldehydes are produced in excellent yields and exhibit a large substrate scope. β-Amino acids and alcohols are synthesized by oxidation or reduction and subsequent deprotection.