Enantioselective synthesis of α-hydroxy thioesters via oxazaborolidine- mediated reduction of α-phenylthio enones

Article abstract of DOI:10.1016/S0040-4039(98)00170-1

α-Phenylthio-α,β-alkenones (2), readily available by Pd(II)-catalysed coupling of (E)-1 phenylthio-1-tributylstannylhex-1-ene with the corresponding acid chlorides have been treated with borane in the presence of phenylglycine- or proline-derived oxazaborolidines to afford 2-phenylthio-2- alken-1-ols (3) with good to excellent enantioselectivities. Ozonolysis of 3 provides a new and efficient route to chiral α-hydroxy thioesters 4.