An efficient and versatile synthesis of 3-alkyl-and 3-alkenyl-5-hydroxycyclopent-2-enones is described. The key intermediate, 4-(t-butyldimethylsilyloxy)-3-methoxycyclopent-2-enone (5), is prepared in five steps from phenol. 1, 2-Addition of various organolithium and Grignard reagents yields tertiary alcohol intermediates which afford the title compounds after solvolysis and desilylation.
