Convenient method for the preparation of 1-phenylthio-3-alken-1-ynes and 4-hydroxy-1-phenylthio-1,2-alkadienes from a common precursor
作者:Atsushi Ogawa、Kazunari Sakagami、Akiko Shima、Hitoshi Suzuki、Satsuki Komiya、Yoshinori Katano、Oyo Mitsunobu
DOI:10.1016/s0040-4039(02)01380-1
日期:2002.9
4-Hydroxy-1-phenylthio-2-alkynes (5) reacted with dihydropyran to afford the corresponding 4-tetrahydropyranyloxy derivatives which, on treatment with KHMDS, gave a mixture of (E)- and (Z)-1-phenylthio-3-alken-1-ynes, with the former predominant. When MeLi was used in the place of KHMDS, the (Z)-isomers were formed in preference to the (E)-isomers. Further treatment of the mixture with a base converted the (Z)-isomers into (E)-isomers. On the other hand, the reaction of 5 with KHMDS gave the corresponding 4-hydroxy-1-phenythio-1,2-alkadienes. (C) 2002 Elsevier Science Ltd. All rights reserved.