Cyclizations of N-carbamoyl and N-thiocarbamoyl iminium ions leading to ring-fused heterocycles

TETRAHEDRON LETTERS

卷:57

Article

Qarah, Ahmad¹  Klumpp, Douglas A.¹ 

[1] Northern Illinois Univ, Dept Chem & Biochem, De Kalb, IL 60115 USA

关键词: Heterocycles;    Superacid;    N-Acyliminium ion;    Electrophile;    Cyclization;   

DOI  :  10.1016/j.tetlet.2016.09.026

来源: Elsevier

【 摘 要 】

gamma-Ureidoacetals react in excess acid to give ring-fused heterocycles (12 examples, 46-93% yields) by intramolecular cyclizations. A mechanism is proposed involving N-carbamoyl iminium ions and related species. The mechanism is further examined by DFf calculations. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

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