Radiochemical Study of the Reactions of Diethylsilylium Ions with Hexamethyldisilazane and Isobutylamine in the Gas Phase
作者:D. V. Vrazhnov、T. A. Kochina、E. N. Sinotova、I. S. Ignat'ev、E. O. Kalinin
DOI:10.1007/s11176-005-0436-2
日期:2005.9
Ion-molecule reactions of diethylsilylium ions with hexamethyldisilazane and isobutylamine were studied radiochemically. These reactions, like the previously studied reactions of diethylsilylium ions with tert-butylaminotrimethylsilane, occur exclusively along the condensation pathway; in both cases, the diethylsilylium ion undergoes a rearrangement. The extremely low degree of rearrangement of the diethylsilylium ion and high yield of the labeled substrate in the reaction with isobutylamine are due to the presence of two labile N-H hydrogen atoms, resulting in active isotope exchange between the Si-T tritium atoms and N-H hydrogen atoms and in shorter lifetime of the condensation complex, caused by more intense bimolecular deprotonation of the complex.
通过放射化学方法研究了二乙基硅鎓离子与六甲基二硅氮烷和异丁胺的离子分子反应。这些反应与之前研究的二乙基硅鎓离子与叔丁胺三甲基硅烷的反应一样,完全沿着缩合途径发生;在这两种情况下,二乙基硅鎓离子都发生了重排。在与异丁胺的反应中,二乙基硅鎓离子的重排程度极低,标记底物的产率很高,这是因为存在两个易变的 N-H 氢原子,导致 Si-T 氚原子和 N-H 氢原子之间的同位素交换活跃,以及缩合络合物的双分子去质子化作用更强烈,从而缩短了缩合络合物的寿命。