data. The Mo–Ccaro, distance of 2.232(2)Å is ca. 0.06 Å shorter than in the cis isomer. The Mo–CO length of 2.001(2)Å compares with the Mo–CO (trans CO) and Mo–CO (trans carbene) lengths of 2.028(3) and 1.980(3)Å respectively in the cis isomer. The activation energy (70.4 ± 2 kJ mol–1, or 74.7 ± 0.7 kJ mol–1 for the ethyl homologues) for the trans→cis isomerisation was measured in diethyl phthalate by
标题化合物的晶体是单斜晶,空间群C 2 / m,a = 14.706(5),b = 7.866(3),c = 8.132(3)Å,β= 114.40(2)。该分子与晶体镜面上的两个卡宾
配体位于2 / m对称的位点(即它们不正交)。对于87个变量(包括各向同性氢原子)和1 661个数据,通过全矩阵最小二乘法将结构精炼为R值为0.027。在Mo-C卡洛,2.232的(2)距离A是CA。比顺式短0.06Å异构体。Mo–CO长度为2.001(2)Å ,而顺式异构体的Mo–CO(反式CO)和Mo–CO(反式卡宾)长度分别为2.028(3)和1.980(3)Å 。使用数字数据记录设备和计算机程序通过差示扫描量热法在
邻苯二甲酸二乙酯中测量反式→顺式异构化的活化能(对于乙基同系物为70.4±2 kJ mol –1或对于乙基同系物为74.7±0.7 kJ mol –1)。反应是一级反应,负活化熵归因于与过渡态溶剂分子的相互作用。