Investigation of pyramidal inversion of nitrogen atom in carbamate and thiocarbamate ions formed at the reaction of СО2, СOS, CS2 with 2-aminoethanol
作者:V. P. Talsi、S. N. Evdokimov
DOI:10.1134/s1070428017110021
日期:2017.11
pyramidal inversion of the nitrogen atom in carbamate and thiocarbamate anions formed at the reaction of 2-aminoethanol with CO2 and COS. The refinement was introduced in formerly suggested cyclic structures of anions containing an intramolecular hydrogen bond NH···O(S), which contradicted the found large values of the barrier of inversion (ΔG ≠ ∼ 70 kJ mol–1). The hydrogen bond in the cyclic anions of
用动态核磁共振(NMR)测定2-氨基乙醇与CO 2和COS反应生成的氨基甲酸酯和硫代氨基甲酸酯阴离子中氮原子的金字塔倒置的势垒高度的ΔG ≠值。含有分子内氢键NH···O(S)的阴离子的环状结构,与发现的较大的反转位阻值(ΔG ≠〜70 kJ mol –1 )。氨基甲酸酯和硫代氨基甲酸酯的环状阴离子中的氢键为两个电子和三个中心。在二硫代氨基甲酸酯阴离子(2-氨基乙醇与CS 2反应的产物)的情况下,不会形成具有多中心氢键的类似环状结构。