Synthesis of (α,α-Difluoropropargyl)phosphonates via Aldehyde-to-Alkyne Homologation
作者:Romana Pajkert、Gerd-Volker Röschenthaler
DOI:10.1021/jo400198a
日期:2013.4.19
3-dibromodifluoroallyl)phosphonate with potassium tert-butoxide gave rise to the corresponding bromoalkyne, whereas upon treatment with lithium base, the generation of ((diethoxyphosphoryl)difluoropropynyl)lithium has been achieved for the first time. The synthetic potential of this lithium reagent was further demonstrated by its reactions with selected electrophiles such as aldehydes, ketones, triflates, chlorophosphines
描述了一种有效的合成方法,该方法适用于一系列从(二乙氧基磷酰基)二氟乙醛开始的Corey-Fuchs型序列,具有二氟亚甲基膦酸酯功能的新型炔烃。叔碳酸钾对中间体(3,3-二溴二氟烯丙基)膦酸酯的脱氢溴化作用-丁氧基生成相应的溴代炔,而在用锂碱处理后,首次实现了((二乙氧基磷酰基)二氟丙炔基)锂的生成。该锂试剂的合成潜力进一步通过其与选定的亲电子试剂(如醛,酮,三氟甲磺酸酯,氯膦和氯硅烷)的反应来证明,从而以良好至极好的收率生成相应的炔丙基膦酸酯。然而,就位阻醛而言,(α-氟代烯丙基)膦酸酯是唯一分离的产物。