A new route for the synthesis of (<i style="">R</i>)-glyceraldehyde acetonide: A key chiral building block

260-263A new route for the synthesis of (R)-glyceraldehyde acetonide via asymmetric dihydroxylation of allyl 4-methoxybenzoate using the (DHQ)2PHAL, K2OsO4·2H2O catalyst system is described. This route involves the asymmetric dihydroxylation of allyl 4-methoxybenzoate, acetonide protection of vicinyl dihydroxyl groups followed by cleavage of p-methoxybenzoate ester and subsequent oxidation to give the (R)-glyceraldehyde acetonide