Pummerer reaction of 2-vinylcyclopropyl sulfoxides: generation and reactions of butadienylthionium ion intermediates
作者:Tetsuo Iwama、Harutoshi Matsumoto、Hiroshi Shimizu、Tadashi Kataoka、Osamu Muraoka、Genzoh Tanabe
DOI:10.1039/a708724a
日期:——
complicated, benzothiazinone derivatives 10 smoothly react with trifluoroacetic anhydride to give 1,3-dienes in good yields. The reactions proceed via butadienylthionium ions by proton abstraction from the 2′-methyl group or the cyclopropane ring. Reactions of disubstituted benzothiazinones 10e–h provided cyclic dienes while treatment of mono- or un-substituted derivatives gave acyclic conjugated dienes
已经研究了2-乙烯基环丙基亚砜的Pummerer反应中丁二烯基硫鎓离子的产生。尽管2-乙烯基环丙基亚砜1的Pummerer反应是复杂的,但是苯并噻嗪酮衍生物10与三氟乙酸酐平稳地反应以高收率得到1,3-二烯。反应通过通过从2'-甲基或环丙烷环中提取质子来获得丁二烯基硫鎓离子。双取代苯并噻嗪酮10e-h的反应提供了环状二烯,而单或未取代衍生物的处理则产生了非环状共轭二烯11a-d。分别通过相应的2-乙烯基环丙基硫化物19和23的MCPBA氧化制得2-乙烯基环丙基亚砜1和10,它们是通过5,6-二氢-2与1,3-二烯通过α-氯代硫化物的环丙烷化而制得的。H-硫代ran中间体22。