Competition between SRN1,SN2 and SRN1 mechanisms is discussed according to the stereochemical results in the alkylation of anions by optically active secondary p-nitrobenzyl reagents. Results from alkylation of the anions of benzylcyanide C and α-aminonitrile A by p-nitrobenzyl chloride 2 rule out SN2 and SRN2 mechanisms. On the other hand, the SN2 process becomes exclusive in O-and C-alkylation of
根据立体
化学结果,通过旋光性对硝基苄基试剂对阴离子进行烷基化,讨论了S RN 1,S N 2和S RN 1机理之间的竞争。从
苯乙腈的阴离子的烷基化结果Ç和α
氨基腈甲由p硝基苄
氯2规则输出S Ñ 2和S RN 2点的机制。另一方面,S N 2过程在
乙酰乙酸酯阴离子B的O-和C-烷基化中被p排斥。-硝基苄基phospho盐,并且该结果表明可以在不消旋的情况下获得对硝基苄基烷基化产物。卤化物2对阴离子B的C-烷基化反应涉及S N 2电子转移竞争。整个结果表明,立体
化学方法提供了有关这些反应机理的精确信息。