AN IMPROVED SYNTHESIS OF (+/-)-METHYL SHIKIMATE THROUGH STEREOSELECTIVE CIS-DIHYDROXYLATION OF (+/-)-METHYL 5β-HYDROXYCYCLOHEXA-1,3-DIENOATE UNDER PREVOST'S REACTION CONDITIONS

Article abstract of DOI:10.1016/S0040-4020(01)91255-4

A Prevost-type reaction under "wet" conditions upon the O-t-butyl-dimethylsilyl derivative of (+/-)-methyl 5β-hydroxycyclohexa-1,3-dienoate gives (+/-)-methyl 3α-acetoxy-4β-hydroxy-5β-t-butyldimethylsilyloxycyclohexene which may be readily deprotected to afford (+/-)-methyl shikimate in very high yield.Less selectivity is observed in a similar reaction upon the parent alcohol and when this compound is reacted under dry conditions the major product is (+/-)-methyl 4β,5β-epoxy-3β-acetoxycyclohexenoate.An analysis of Prevost reactions with exo and endo methyl 7-oxabicyclo<2,2,1>hept-5-en-2-oate is also described.