Kinetic isotope effects of nitrogen and hydrogen in reaction of N-tert-butyl-P-phenylphosphonamidothioic acid with alcohols
作者:Stefan Jankowski、Adam Mazur、Tomasz Nonas、Barbara Vokal
DOI:10.1016/j.jorganchem.2004.09.025
日期:2005.5
Nitrogen and hydrogen isotope effects for the reaction of N-tert-butyl-P-phenylphosphonamidothioic acid 1 with alcohols (methanol, butanol, iso-propanol, tert-butanol) were measured in dichloromethane at 30 °C. The observed nitrogen isotope effect k14/k15 is only slightly sensitive to a steric hindrance of the alcohol [1.0070 ± 0.0002 (MeOH), 1.0074 ± 0.0004 (BuOH), 1.0062 ± 0.0004 (PriOH), 1.0087 ± 0
为的反应氮气和氢气同位素效应N-叔丁基- P -phenylphosphonamidothioic酸1与醇(甲醇,丁醇,异丙醇,叔在二氯甲烷,测定在30丁醇)℃。观察到的氮同位素效应k 14 / k 15对醇的空间位阻仅稍敏感[1.0070±0.0002(MeOH),1.0074±0.0004(BuOH),1.0062±0.0004(Pr i OH),1.0087±0.0007(Bu t OH)]。通过逆氢效应k ROH /证明了质子从氧气转移到氮气的预平衡步骤ķ ROD [0.778±0.052(MeOH)中,0.863±0.063(丁醇),0.883±0.080(镨我OH),0.746±0.084(BU吨OH)]。对于消除加成机理和偏硫代膦酸酯PhPSO中间体,实验值与PM3水平的半经验计算的理论结果一致。对于与甲醇的反应,加成消除机理也是可能的。