A novel stereoselective synthesis of (<i>Z</i>)-α-arylsulfanyl-α,β-unsaturated ketones via Stille coupling of (<i>E</i>)-α-arylsulfanylvinylstannanes with acyl halides
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