Chlorotropylium Promoted Conversions of Oximes to Amides and Nitriles

• Published in: European journal of organic chemistry Vol. 2020; no. 3; pp. 311 - 315
• Main Authors: Xu, Jiaxi, Gao, Yu, Li, Zhenjiang, Liu, Jingjing, Guo, Tianfo, Zhang, Lei, Wang, Haixin, Zhang, Zhihao, Guo, Kai
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 23.01.2020; Wiley Subscription Services, Inc
• Subjects: Aldehydes; Amides; Bifurcations; Chemistry; Chemistry, Organic; Dehydration; Ethers; Ketones; Nitriles; Organocatalysis; Oximes; Physical Sciences; Rearrangement; Science & Technology; Tropylium; Oximes; EPSILON-CAPROLACTAM; ACTIVATION; CARBOCATION; Tropylium; KETOXIMES; Amides; Organocatalysis; MILD; DEHYDRATION; CATION; ALDOXIMES; Rearrangement; BECKMANN REARRANGEMENT; CYANURIC CHLORIDE
• ISSN: 1434-193X; 1099-0690
• DOI: 10.1002/ejoc.201901537

Chlorotropylium chloride as a catalyst for the transformations of oximes, ketones, and aldehydes to their corresponding amides and nitriles in excellent yields (up to 99 %) and in short reaction times (mostly 10–15 min). Oximes were electrophilically attacked on the hydroxyl oxygen by chlorotropylium. The produced tropylium oxime ethers were the key intermediates, of which the ketoxime ether led to amide through Beckmann rearrangement, and the aldoxime ether led to nitrile by nitrogen base DBU assisted formal dehydration. This chlorotropylium activation protocol offered general, mild, and efficient avenues bifurcately from oximes to both amides and nitriles by one organocatalyst. Chlorotropylium chloride as a catalyst for the transformations of oximes, ketones, and aldehydes to their corresponding amides and nitriles in excellent yields (up to 99 %) and in short reaction times (mostly 10–15 min). Oximes were electrophilically attacked on the hydroxyl oxygen by chlorotropylium.