bornene (2). The iodo ether cyclization of 2 can convert only endo-5-(2-hydroxyethyl)-2-norbornene (2b) to iodo ether 10, followed by reductive elimination and subsequent dehydration to furnish endo-5-vinyl-2-norbornene (1b) which has not been isolated in pure form. Meanwhile, unreacted exo-5-(2-hydroxyethyl)-2-norbornene (2a) produces exo-5-vinyl-2-norbornene (1a) via dehydration.
5-
乙烯基-2-
降冰片烯 (1) 与 9-BBN 的
硼氢化反应主要提供 5-(2-羟乙基)-2-
降冰片烯 (2)。2 的
碘醚环化只能将内-5-(2-羟乙基)-2-
降冰片烯 (2b) 转化为
碘醚 10,然后还原消除并随后脱
水以提供内-5-
乙烯基-2-
降冰片烯 (1b) ) 尚未以纯形式分离。同时,未反应的外-5-(2-羟乙基)-2-
降冰片烯(2a)通过脱
水产生外-5-
乙烯基-2-
降冰片烯(1a)。