The reaction of aroylketene dithioacetals 1 with Vilsmeier-Haack reagent, prepared from POCl3 and DMF, under mild conditions gave 2-aroyl-3,3-bis(alkylsulfanyl)acrylaldehydes 2 in excellent yields. Cyclization of 2-[2-aroyl-3,3-bis(methylsulfanyl)-2-propylidene]malononitriles 3, derived from 2 and malononitrile, in the presence of concentrated hydrochloric acid in tertiary butanol afforded 2-pyridone derivatives 4.
对芳酰基烯二
硫乙酯1与由POCl3和
DMF制备的Vilsmeier-Haack试剂在温和条件下反应,得到了优良产率的2-芳酰基-3,3-双(烷基
硫基)
丙烯醛2。由2和马来腈衍生的2-[2-芳酰基-3,3-双(甲基
硫基)-2-
丙烯基]马来腈3在浓
盐酸和
叔丁醇存在下环化,得到2-
吡啶酮衍
生物4。