Inapplicability of the Antiperiplanar Lone Pair Hypothesis to C−P Bond Breaking and Formation in Some S−C−P<sup>+</sup> Systems
作者:Piotr P. Graczyk、Marian Mikolajczyk
DOI:10.1021/jo941771m
日期:1996.1.1
in the course of the reaction. Stereoelectronic control of the C(2)-P bond breaking and formation results from interplay of several factors. The role of the n(S)-sigma(C(2))(-)(P) and sigma(C(4,6))(-)(S)-sigma(C(2))(-)(P) hyperconjugation, as well as of the repulsive interactions between lone electron pairs pi(S) of endocyclic sulfur atoms and pi-electrons of the phenyl ring(s) connected with phosphorus
根据反周平面孤对假说,SCP(+)系统中的C(2)-P键断裂和形成都不会发生。使用5-叔丁基-1,3-二硫杂环丁烷和顺式4,6-二甲基-1,3-二硫杂环丁烷的2-膦酰基衍生物进行的实验不利于高能船用构象异构体作为反应性中间体的参与。所获得的结果支持在反应过程中进行构象调整的可能性。C(2)-P键断裂和形成的立体电子控制是由几个因素的相互作用引起的。n(S)-sigma(C(2))(-)(P)和sigma(C(4,6))(-)(S)-sigma(C(2))(-)(讨论了P)的超共轭作用以及内环硫原子的孤电子对pi(S)与与磷连接的苯环的pi电子之间的排斥相互作用。