[2 + 2] Annulation of Aldimines with Sulfonic Acids: A Novel One-Pot cis-Selective Route to β-Sultams
作者:Ankita Rai、Vijai K. Rai、Atul K. Singh、Lal Dhar S. Yadav
DOI:10.1002/ejoc.201100628
日期:2011.8
A novel DMF/dimethyl sulfate promoted [2 + 2] annulation of aldimines with sulfonic acids afforded β-sultams in good to excellent yields (35–93 %) under mild conditions. The protocol offers a convenient alternative to highly corrosive and hygroscopic sulfonyl chlorides to provide β-sultams with complete diastereoselectivity in favour of the cis isomers.
新型 DMF/硫酸二甲酯促进了醛亚胺与磺酸的 [2 + 2] 环化,在温和条件下以良好至极好的产率 (35-93%) 提供了 β-磺胺嘧啶。该协议为高腐蚀性和吸湿性磺酰氯提供了一种方便的替代方案,以提供具有完全非对映选择性的 β-sultams,有利于顺式异构体。