Mj. Gaunt et al., Evidence that the availability of an allylic hydrogen governs the regioselectivity of the Wacker oxidation, CHEM COMMUN, (18), 2001, pp. 1844-1845
The allylic hydrogen is found to have a dramatic effect on the regioselecti
vity of the Wacker oxidation, leading to the postulation that an agostic hy
drogen or enyl (sigma+pi) complex helps to stabilise the key intermediate.