作者:Annette D. Allen、Thomas T. Tidwell
DOI:10.1021/jo982054l
日期:1999.1.1
contrast to previous studies of Ph(2)C=C=O and other reactive ketenes in which only a first-order dependence on [amine] was observed in H(2)O or in CH(3)CN. Derived third-order rate constants for 6 depend on the amine basicity, with a 1.7 x 10(7) greater reactivity for n-BuNH(2) compared to CF(3)CH(2)NH(2). These kinetic results are consistent with recently reported theoretical studies for reaction of CH(2)=C=O
与之形成鲜明对比的是,PhMe(2)SiCH = C = O(6)与胺在CH(3)CN中形成酰胺反应的速率常数最适合与[胺]混合的二阶和三阶依赖性以前对Ph(2)C = C = O和其他反应性烯酮的研究,其中在H(2)O或CH(3)CN中仅观察到对[胺]的一级依赖。派生的6的三阶速率常数取决于胺的碱性,与CF(3)CH(2)NH(2)相比,n-BuNH(2)具有1.7 x 10(7)更大的反应性。这些动力学结果与最近报道的CH(2)= C = O与NH(3)反应的理论研究相一致。对于6,在CH(3)CN中的相对反应性k(n-BuNH(2))/ k(H(2)O)估计为10(13)。拥挤的乙烯酮t-Bu(2)C = C = O(10)极易失活并发生胺化反应,在纯正n-BuNH(2)中的反应速率比10-12慢10(12)和2 x 10(5)倍。 t-BuCH = C = O和t-BuC(i-Pr)=