Chalcogenation of the 1,4-C<sub>2</sub>P<sub>4</sub> Ring: Oxidation, Isomerization, Insertion, and Ring Contraction
作者:Philip J. W. Elder、Tristram Chivers
DOI:10.1021/ic401002b
日期:2013.7.1
excess of chalcogen, the five-membered rings (H2C)(PtBuE)2E2 (E = S, 5a, E = Se, 5b) were also observed; the X-ray structure of 5b revealed a half-envelope conformation for the CP2Se2 ring. The direct reaction of 4a with sulfur in boiling toluene does not produce 5a, whereas 5b is formed slowly and in low yields from 4b and selenium under similar conditions. On the basis of DFT calculations of the relative
H的反应2 C(的PCl 2)2与4当量的吨的四氢呋喃(THF)BuMgCl产生1,4 -(CH 2)2(P吨丁基)4,1,在约65%的产率。该六元环在低温下与甲苯中的元素硫或硒直接反应,生成一元和二卤化物1,4 --(CH 2)2(P t BuE)(P t Bu)3(E = S,2a,E = Se,2b)和1,4-(CH 2)2-2,5-(P t BuE)2(P t Bu)2(E = S,3a,E = Se,3b)。X射线结构测定表明3a和3b在固态是同构的。六元C 2 P 4环表现出扭转舟的几何形状,在每种情况下,硫属元素取代基均位于顺式位置。进行了三种可能的破坏性异构体的密度泛函理论(DFT)计算,以阐明有利于2,5-异构体的因素。在3b或3a溶液中观察到热异构现象分别在60和95°C的甲苯中溶解,得到相应的2,6-异构体。在回流下,在甲苯中有过量硫族元素的情况下,获得了四元环(H 2