Intramolecular Cyclizations of<i>o</i>-Substituted<i>β</i>,<i>β</i>-Difluorostyrenes: Synthesis of 3-Fluorinated Isochromenes and Isothiochromenes
作者:Yukinori Wada、Junji Ichikawa、Tadayuki Katsume、Tomoko Nohiro、Tatsuo Okauchi、Toru Minami
DOI:10.1246/bcsj.74.971
日期:2001.5
an oxygen (OH) or a sulfur (SH, SCOCH3) nucleophile linked by a methylene unit to the ortho carbon are prepared from 2,2,2-trifluoroethyl p-toluenesulfonate via the in situ generation of 2,2-difluorovinylboranes and their palladium-catalyzed cross-coupling reaction with aryl iodides. These styrene derivatives readily undergo intramolecular nucleophilic substitution of the oxygen and sulfur with loss
带有氧 (OH) 或硫 (SH, SCOCH3) 亲核试剂的 β,β-二氟苯乙烯通过亚甲基单元与邻位碳连接,由对甲苯磺酸 2,2,2-三氟乙酯通过原位生成 2, 2-二氟乙烯基硼烷及其与芳基碘化物的钯催化交叉偶联反应。这些苯乙烯衍生物在碱性条件下很容易发生氧和硫的分子内亲核取代而失去氟,从而以高产率生成 3-氟异色烯和 3-氟异硫色烯。