The Mechanism of Phosphonium Ylide Alcoholysis and Hydrolysis: Concerted Addition of the O−H Bond Across the P=C Bond
作者:Peter A. Byrne、Declan G. Gilheany
DOI:10.1002/chem.201600530
日期:2016.6.27
protonation of ylide. Therefore, we propose concerted addition of the water or alcohol O−H bond across the ylide P=C bond. In support of this, we provide NMR spectroscopic evidence for equilibrium between ylide and aclohol that does not require the involvement of phosphonium hydroxide. We report the first P‐alkoxyphosphorane to be characterised by NMR spectroscopy that does not undergo exchange on
关于磷鎓叶立德的水解和醇解反应的先前工作在其目前公认的机理的背景下进行了总结和综述。与叶立德水解以及盐和叶立德醇解有关的一些实验事实表明与这些机理相冲突。特别是,我们证明了水和醇的p K a值在有机介质中过高,无法引起叶立德的质子化。因此,我们建议水合或醇O-H键在叶立德P = C键上协同加成。为了支持这一点,我们提供了NMR光谱证据,表明不需要氢氧化hydroxide参与的叶立德和醇之间的平衡。我们报告第一个P-烷氧基磷烷可以通过NMR光谱进行表征,而无需在NMR时标上进行交换。二维NMR光谱技术已首次应用于对P-烷氧基磷光烷的表征。