Population ratios of rotational isomers in substituted 9-benzyl-8,13-dichloro-1-methyltriptycenes were examined by equilibration in solution. The sc isomers increase in their populations as the electron density on the 9-benzyl group increases and the acidity of the 1-methyl group increases. The sc/ap ratios were larger than 2, the statistical value, in all the compounds examined, except the 4-nitrobenzyl
取代的 9-benzyl-8,13-dichloro-1-methyltriptycenes 中旋转异构体的总体比率通过溶液中的平衡来检测。随着 9-
苄基上的电子密度增加和
1-甲基的酸度增加,sc 异构体的数量增加。除了 4-硝基
苄基化合物外,所有检测的化合物的 sc/ap 比率均大于 2,即统计值。相比之下,
MM2 计算表明 sc 异构体比 ap 不稳定。1 kcal mol−1。这种差异以及对旋转异构体种群的替代效应归因于主要通过电荷转移相互作用稳定系统的 sc 形式中
CH3…π 相互作用的存在,但不包括在
MM2 计算中。