Cyclization and N‑Iodosuccinimide-Induced Electrophilic Iodocyclization of 3‑Aza-1,5-enynes To Synthesize 1,2-Dihydropyridines and 3‑Iodo-1,2-dihydropyridines

• Published in: Journal of organic chemistry Vol. 78; no. 8; pp. 4065 - 4074
• Main Authors: Xin, Xiaoyi, Wang, Dongping, Wu, Fan, Li, Xincheng, Wan, Boshun
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 19-04-2013
• Subjects: Alkynes - chemical synthesis; Alkynes - chemistry; Aza Compounds - chemical synthesis; Aza Compounds - chemistry; Cyclization; Dihydropyridines - chemical synthesis; Dihydropyridines - chemistry; Molecular Structure; Succinimides - chemistry
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo400387b

Metal-free cyclization and N-iodosuccinimide-induced electrophilic iodocyclization of readily available 3-aza-1,5-enynes have been developed. The reactions selectively give 1,2-dihydropyridines and 3-iodo-1,2-dihydropyridines involving an aza-Claisen rearrangement and a 6π-electrocyclization step. Furthermore, the reaction could be carried out in 10 g scale for the synthesis of 1,2-dihydropyridines.