State Key Laboratory of Fine Chemicals, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, Liaoning, P.R. China.
Org Biomol Chem. 2020 Mar 14;18(10):1933-1939. doi: 10.1039/d0ob00057d. Epub 2020 Feb 26.
A novel and convenient photo-mediated halogenated spirocyclization of N-(p-methoxyaryl)propiolamides has been developed. The photolysis of phenyliodine bis(trifluoroacetate) (PIFA) as an iodination reagent led to iodinated ipso-cyclization under the irradiation of a xenon lamp, while brominated ipso-cyclization or chlorinated ipso-cyclization was achieved by irradiating a mixture of PIFA and KBr/KCl under a blue LED. The present protocol simply utilizes light as the safe and clean energy source and doesn't require any external photocatalyst providing various 3-halospiro[4,5]trienones in good to excellent yields (up to 93%).
一种新颖且便捷的通过光介导的 N-(对甲氧基芳基)丙炔酰胺的卤代螺环化反应被开发出来。作为碘化试剂的苯碘二(三氟乙酸酯)（PIFA）在氙灯照射下发生光解，导致碘代环化，而在蓝 LED 照射下，PIFA 和 KBr/KCl 的混合物则发生溴代或氯代环化。本方法简单地利用光作为安全清洁的能源，不需要任何外部光催化剂，以良好至优秀的收率（高达 93%）提供了各种 3-卤代螺[4,5]三烯酮。
