A comparative study of the interaction of salicylaldehydes with phosphonoacetates under Knoevenagel reaction conditions. Synthesis of 1,2-benzoxaphosphorines and their dimers
作者:Anka Bojilova、R. Nikolova、Christo Ivanov、Nestor A. Rodios、A. Terzis、C.P. Raptopoulou
DOI:10.1016/0040-4020(96)00748-x
日期:1996.9
The reaction of salicylaldehydes 5 with phosphonoacetates 6 gives the coumarin-3-phosphonates 7 and the 1,2-benzoxaphosphorine-3-carboxylates 8 in yields and 7:8 ratios depending on the reaction conditions. A mechanistic explanation is given for the stereoselectivity of these reactions. Irradiation of compounds 8 or direct exposure to sunlight causes their head-to-tail dimerization, giving the dimers
水杨醛5与膦酰基乙酸酯6的反应产生香豆素3-膦酸酯7和1,2-苯并氧杂膦基-3-羧酸酯8,其产率和反应比取决于反应条件为7:8。对这些反应的立体选择性给出了机械的解释。化合物8的照射或直接暴露在阳光下会导致它们的头到尾二聚化,从而得到二聚体11,在一种情况下,得到其磷差向异构体12。通过X射线晶体学分析证实了它们的结构。对化合物7、8、11和还讨论了图12。