A chiral (1R,2R)-diaminocyclohexane-derived bisthiourea was found to exhibit a significant asymmetric induction in the intramolecular [2+2] photocycloaddition of 2,3-dihydropyridone-5-carboxylates. Under optimized conditions the reaction was performed with visible light employing 10 mol% thioxanthone as triplet sensitizer. Due to the different electronic properties of its carbonyl oxygen atoms, a directed
发现手性(1R,2R)-二
氨基
环己烷衍生的双
硫脲在2,3-
二氢吡啶酮-5-
羧酸酯的分子内[2 + 2]光环加成中表现出显着的不对称诱导。在优化的条件下,反应是在可见光下使用10摩尔%
噻吨酮作为三重态敏化剂进行的。由于其羰基氧原子的电子特性不同,因此可以将底物定向结合到模板上,从而可以实现有效的对映体区分。