A readily accessible conjugate-base-stabilized carboxylic acid (CBSCA) catalyst facilitates highly enantioselective [4+2] cycloaddition reactions of salicylaldehyde-derived acetals and cyclic enol ethers, resulting in the formation of polycyclic chromanes with oxygenation in the 2- and 4-positions. Spirocyclic products are also accessible.
一种易于获得的共轭碱稳定的
羧酸 (C
BSCA) 催化剂可促进
水杨醛衍生的
缩醛和环状烯醇醚的高度对映选择性 [4+2] 环加成反应,从而在 2- 和 4- 氧化中形成多环苯并二氢
吡喃。职位。螺环产品也是可用的。