Structure and properties of phosphonium ylides-betaines, derivatives of 2-phenyl-2-oxazolin-5-one and its thio- and seleno-analogues
作者:Luc Van Meervelt、Geertrui S. Schuerman、Vladimir S. Brovarets、Nikolai I. Mishchenko、Evgenii A. Romanenko、Boris S. Drach
DOI:10.1016/0040-4020(94)01041-w
日期:1995.1
investigation has shown that the structure and properties of mesomeric triphenylphosphonium ylides containing the 5-oxo-2-phenyl-4-oxazolidene moiety undergo considerable changes when the carbonyl oxygen atom is replaced by sulfur or selenium. This substitution leads to a clear decrease of the contribution of the ylide structure and an increased importance of the betaine structure, in contradiction with
化学,光谱和X射线的综合结构研究表明,当羰基氧原子被硫或硫取代时,含有5-氧代-2-苯基-4-恶唑烷部分的三聚体三苯基phosph基化物的结构和性质发生相当大的变化。硒。与O> S> Se系列的电负性降低相反,这种取代导致内酯结构的贡献明显减少,甜菜碱结构的重要性增加,但与这些双键形成的不同能力有关。元素。硫代或硒代羰基使叶立德位点失活已应用于区域选择性合成。