Influence of α-methyl substitution of proline-based organocatalysts on the asymmetric α-oxidation of aldehydes
作者:Sok-Teng (Amy) Tong、Margaret A. Brimble、David Barker
DOI:10.1016/j.tet.2009.04.060
日期:2009.6
The direct asymmetric organocatalytic α-oxidation of aldehydes using trans-2-(p-methylphenylsulfonyl)-3-phenyloxaziridine is reported. This method affords the S isomer of α-hydroxy aldehydes, thereby complementing the selectivity for the R isomer observed using the two-step nitrosobenzene method. Use of α-methylproline and α-methylproline tetrazole significantly increases the enantioselectivity observed
报道了使用反式2-(对甲基苯基磺酰基)-3-苯基恶二氮丙啶对醛的直接不对称有机催化α-氧化。该方法提供了α-羟基醛的S异构体,从而补充了使用两步亚硝基苯方法观察到的R异构体的选择性。与类似的未取代的有机催化剂相比,使用α-甲基脯氨酸和α-甲基脯氨酸四唑显着提高了醛的α-氧化观察到的对映选择性。