A Facile Synthesis of (+)- and (-)-Shikimic Acid with Asymmetric Deuterium Labeling, Using Tricarbonyliron as a Lateral Control Group

Article abstract of DOI:10.1021/jo00237a010

(-)-Methyl shikimate has been prepared from tricarbonyliron complexes of methyl dihydrobenzoate.Reaction of optically pure (+)-tricarbonyl(1-carbomethoxycyclohexa-1,3-dienyl)iron hexafluorophosphate with hydroxide ion and then tert-butyldimethylsilyl chloride (TBDMSCl) followed by metal removal with Me3NO gave (+)-1-carbomethoxy-5-hydroxycyclohexa-1,3-diene as its TBDMS ether.Osmium tetraoxide oxidation and then desilylation gave optically pure (-)-methyl shikimate.Also, fully resolved (-)-tricarbonyl(1-carbomethoxycyclohexa-1,3-dienyl)iron hexafluorophosphate was hydroxylated and then treated with CrO3 followed successively by ZnBH4 and TBDMS triflate.Demetalation gave the same TBDMS-protected (+)-1-carbomethoxy-5-hydroxycyclohexa-1,3-diene as that obtained above by direct reaction.Thus, although resolution is necessary, both enantiomers of tricarbonyl(1-carbomethoxycyclohexa-1,3-dienyl)iron hexafluorophosphate are convertible into natural (-)-methyl shikimate.Deuterium was incorporated enantiospecifically to give (6R)- or (6S)-methyl 6-deuterioshikimate.