The cis/trans ratio as well as trans-(−)-(R:R)/(+)-(S:S) ratio of cyclopropane products in the NaH-catalyzed Michael type condensations of (−)-menthyl chloropropionate with methyl methacrylate, conducted in media of varying dielectric constant, unequivocally showed the dependence of stereoselectivity of the reaction on solvent polarity. The stereochemical results were explicable in terms of electrostatic
该顺/反比率以及反式- ( - ) - (- [R :- [R)/(+) - (小号:小号)在不同介电常数的介质中进行的NaH催化的(-)-薄荷基
氯丙酸酯与
甲基丙烯酸甲酯的Michael型缩合反应中
环丙烷产物的比率明确表明反应的立体选择性对溶剂极性的依赖性。立体
化学结果在静电稳定和假定的过渡态构象中的非键相互作用方面是可解释的,该假定的过渡态构象由速率重叠的立体重叠决定了环化步骤,因此由立体
化学决定了环化步骤。柯克伍德-昂萨格(Kirkwood-Onsager)理论在定量方面也很好地关联了溶剂效应。