Sulphur-oxygen versus carbon-oxygen bond fission in the solvolysis of benzyl sulphenates
作者:S. Braverman、D. Reisman
DOI:10.1016/s0040-4020(01)97079-6
日期:1974.1
While the solvolysis of 1 showed first-order kinetics, the solvolysis of 2 was second-order (first-order with respect to ester and to added base). The solvolysis rate of 2 decreases on going from 100% to 80% ethanol and by using pyridine instead of acetate as base, consistent with an SN2 type mechanism involving nucleophilic displacement at sulphur by the base or lyate ion. The rate of solvolysis of 1 is
相比于对茴香基trichloromethanesulphenate 1,在室温下用碳-氧键断裂,相应的2- nitrobenzenesulphenate的醇解其容易经历乙醇解2个前进以类似的速度仅在100℃,并涉及硫-氧键断裂。1的溶剂分解显示一级动力学,而2的溶剂分解显示二级(相对于酯和添加的碱为一级)。当溶剂从100%变为80%并使用吡啶代替乙酸盐作为碱时,溶剂分解率2降低,这与S N一致2型机制涉及通过碱或裂解物离子在硫原子上进行亲核取代。在极性溶剂中1的溶剂分解速率大大提高,并且与对甲氧基新叶酰基甲苯磺酸盐的电离令人满意地相关。提出了一种离子对某些离子对物质的电离机理,用于1的溶剂分解。