经由α-羰基烯酮环二硫代缩醛的取代-环合芳构化及分解反应

本文报道了芳香族α-羰基烯酮环二硫代缩醛与 2-甲基烯丙基Grignard试剂的1,2-加成产物在酸催化下的取代-环合芳构化反应及分解反应. 探讨了亲核试剂体积, 缩醛基结构对取代-环合芳构化反应活性的影响.

Studies on the substitution-cycloaromatization and decomposition reaction via α-oxo ketene cyclic dithioacetals

Addition of the aromatic α-oxo ketene cyclic dithioacetals with methallyl Grignard reagent afforded the carbinols 3 . Catalyzed by BF~3·Et~2O, carbinols 3 were converted to the corresponding aromatic ethers 4 when the reaction was performed in alcohols used. While catalyzed by silica gel, the β,γ-unsaturated aromatic ketones 6 were obtained from the decomposation of 3. Some effective factors to the substitution-cycloaromatization reaction, such the volum of R^1 and the structure of dithioacetal group, were examined.