Oxidation at the Double Bond of Allylic Alcohols

Despite its apparent lack of involvement, it is clear from stereochemical studies that an allylic hydroxyl group can have a major influence on the result of reactions at the carbon-carbon double bond. Indeed, the hydroxyl group of the allylic alcohol can be used to guide the outcome of the oxidation process. 

The following definitions are taken from Eliel, E. L. Wilen, S.H. Stereochemistry of Organic Compounds, Wiley, 1994, pp. 1996-1997 Enantiomer excess (ee). In a mixture of a pure enantiomer (R or 5) and a racemate (RS), ee is the percent excess of the enantiomer over the racemate. Diastereomer excess (de). In a diastereoselective reaction producing two (and only two) diastereomers in amounts A and B, de = 100 (lA - BI)/(A + B).  

the replacement of a third wopropoxide [-OCH(CH3)2] by the t-butylhydroperoxide [H-0-0-C(CH3)3] oxidizing agent and the introduction of the allylic alcohol [C=C-C-OH] with the loss of the fourth wopropoxide [-OCH(CH3)2] produces an intermediate in which a simple transfer of oxygen from the t-butyl- 

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