Vitamin B12, a Catalyst in the Synthesis of Prostaglandins

Article abstract of DOI:10.1016/S0040-4020(01)85455-7

A prostaglandin F_2α precursor containing all structural features from C6 to C20 with 8R,9S, 11R and 12R chirality is obtained by the one step formation of two C-C bonds in the B₁₂-catalyzed radical cyclization-addition sequence starting from a chiral cyclopentene bromoacetal and 1-octyne-3-one.The B12-catalyzed radical cyclization-elimination sequence of a chiral cyclopentene precursor leads to (-)-(3aR,6aS)-3,3a,6,6a-tetrahydro-2H-cyclopentafuran-2-one.Its (+)-(3aS,6aR)-enantiomer is obtained via B₁₂-catalyzed, enantioselective isomerization of cyclopentene oxide to (R)-2-cyclopentene-1-ol followed by the B₁₂-catalyzed cyclization-elimination sequence of its bromoacetal.