Theoretical Studies on Cycloaddition Reactions of 2-Azaallene Cations with Isocyanates

✍ Scribed by Si-Ya Yang; Cheng-Ke Sun; De-Cai Fang

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 204 KB
• Volume: 2003
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200200650

✦ Synopsis

Abstract

The mechanisms of cycloaddition reactions between 2‐azaallene cations and isocyanates have been explored at the B3LYP/6‐31G* level. It is found that [2+2] or [2+4] cycloaddition reactions can take place via an intermediate when 2‐azaallene cations react with 1 or 2 equiv. of isocyanates. The effects of substituents are also reported in the present paper, and the results obtained indicate that electron‐attracting groups on 2‐azaallene cations favor the reaction, and electron‐donating groups on 2‐azaallene cations hinder the reaction. Substituents on isocyanates have the opposite effects. These results have been rationalized with FMO interaction. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)