Enantio‐ and Diastereoselective, Lewis Base Catalyzed, Cascade Sulfenoacetalization of Alkenyl Aldehydes
作者:Anastassia Matviitsuk、Scott E. Denmark
DOI:10.1002/anie.201906535
日期:2019.9.2
catalytic, enantio-, and diastereoselective formation of sulfenyl acetals bearing multiple stereogenic centers is reported. Alkenyl aldehydes undergo a chiral thiiranium ion initiated cascade starting with intramolecular capture by a formyl group and termination by capture with HFIP solvent. This method provides a one-pot synthesis of dihydropyran and 1,3-disubstituted isochroman acetals in good to excellent
据报道,带有多个立体中心的亚硫基乙缩醛催化,对映体和非对映体选择性形成。烯基醛经历手性噻吩鎓离子引发的级联反应,首先通过甲酰基进行分子内捕获,然后通过用HFIP溶剂捕获而终止。该方法可以一锅法合成二氢吡喃和1,3-二取代的异苯并二氢吡喃缩醛,收率好至极好,非对映异构体含量高(高达> 99:1 dr),对映体控制(高达99:1 er)。