Unexpected opposite stereochemistries and different mechanisms of nucleophilic substitution reactions of homochiral tert-butylphenylthiophosphinoyl chloride and bromide
作者:Jan Omelańczuk、Marian Mikolajczyk
DOI:10.1039/c39940002223
日期:——
(ethylsulfanyl) anion with homochiral (+)-(S)-tert-butylphenylphosphinochloridothionate 2 and (–)-(S)-tert-butylphenylphosphinobromidothionate 3 proceed with inversion and retention at phosphorus, respectively, as a consequence of different reaction mechanisms; the stereoretentive reaction with bromide 3, in contrast to the direct nucleophilic substitution at phosphorus in chloride 2, is a two-step process involving
乙基巯基(乙基硫烷基)阴离子与高手性(+)-(S)-叔丁基苯基膦基氯代硫代硫酸根2和(-)-(S)-叔丁基苯基膦基溴代硫代磺酸根3的反应分别在磷中转化并保留。机制;与溴化物3的立体保持反应不同,与氯化物2中磷的直接亲核取代相反,它是一个分为两个步骤的过程,涉及第一步是EtS的亲核攻击-在正电溴原子上。