Stereocontrolled Synthesis of Prostaglandins from Cyclopentadiene Monoepoxide

Article abstract of DOI:10.1021/jo00200a063

Two complementary syntheses of prostaglandins from the same key intermediate 3, available in four steps from cyclopentadiene monoepoxide, are described.In one approach, a saturated α-chain is introduced via a 1,4-addition of an appropriately functionalized cyanocuprate reagent onto silyl enol ether 3.The resulting prostanoid compound was converted into the bronchodilator 1-decarboxy-1-hydroxymethyl PGE₁, PGE₁, and PGF_1α.The second approach involves the transformation of silyl enol ether 3 into the known prostanoid precursor 11 via selective addition of carbethoxycarbene and subsequent fluoride-induced ring opening of the resulting (silyloxy)cyclopropane carboxylate ester.