Hydroxylation by iodine-silver benzoate Prevost reagent

Hydroxylation by iodine-silver benzoate (Prevost reagent) 

According to Prevost and his collaborators olefins are converted by a solution of the complex compound [(C6H5COO)2Ag]I (obtained from silver benzoate and iodine in benzene) stereospecifically into trans-1,2-benzoates, whence the trans- 1,2-glycols are easily prepared. 

This reaction has been reviewed by Milas.12lb 

Woodward and Brutcher Jr.128 described the conversion of olefins into d,s-a glycols by iodine and silver acetate in aqueous acetic acid. The reaction gives cis-fi-hydroxy -acetates in one operation, and thence hydrolysis affords the ds-flc-glycols. Applications in steroid chemistry129 and elsewhere have given the method general importance130-132 for ds-hydroxylation. 

Woodward ds-hydroxylation is based on the work of Winstein and his co-workers on the neighboring group effect in organic chemistry for a review see Lwowski.133 

---