Molecular iodine (10 mol%) efficiently catalyzes the ring expansion of 4-oxoazetidine-2-carbaldehydes 1 in the presence of tert-butyldimethyl cyanide to afford protected 5-cyano-3,4-dihydroxypyrrolidin-2-ones 2 with good yield and high diastereoselectivity, through a novel C3âC4 bond cleavage of the β-lactam nucleus.
在叔丁基二甲基
氰化物存在下,分子
碘(10 摩尔%)可高效催化 4-氧代氮杂
环丁烷-2-羧醛 1 的扩环反应,通过δ-内酰胺核的新型 C3âC4 键裂解作用,得到受保护的 5-
氰基-3,4-二羟基
吡咯烷-2-酮 2,产率高,非对映选择性强。