Highly Selective Synthesis of [(Z)-3-Chloro-2-(phenylselanyl)-1-alkenyl]phosphonates and 2-Ethoxy-4-(phenylselanyl)-2,5-dihydro-1,2-oxaphosphole 2-Oxides by Electrophilic Reaction of 1,2-Alkadienylphosphonates with PhSeCl
作者:Guangke He、Yihua Yu、Chunling Fu、Shengming Ma
DOI:10.1002/ejoc.200900913
日期:2010.1
interesting to note that the stereo-selctivity for the selenochlorination reaction is opposite to that of the iodo- and selenohydroxylation reactions of (allenyl)diphenylphosphane oxides with Cl- acting as the nucleophile. The stereoselectivity of the cyclization reaction is clearly different from that of the selenochlorination reaction.
单取代的 1,2-链二烯基膦酸酯与 PhSeCl 在 THF 或二恶烷/H 2 O (10:1) 中于 70 °C 反应得到硒氯化产物 [(Z)-3-氯-2-(苯基硒基)-1-烯基]膦酸盐具有非常高的化学选择性和立体选择性,而与二取代和三取代的丙二烯基膦酸盐的相同反应仅提供 2-乙氧基-4-(苯基硒基)-2,5-二氢-1,2-氧杂磷酰 2-氧化物。有趣的是,硒氯化反应的立体选择性与(烯丙基)二苯基膦氧化物的碘和硒羟基化反应相反,Cl-作为亲核试剂。环化反应的立体选择性明显不同于硒氯化反应的立体选择性。