Abstract
According to quantum chemical calculations CAM-B3LYP/6-311++G(d,p) intramolecular migrations of arylazo groups in 5-arylazo-1,2,3,4,5-pentamethoxycarbonylcyclopentadienes occur by a dissociative mechanism through the intermediate formation of tight ionic pairs with low energy barriers: Δ E ≠ZPE, benzonitrile, 14.0 (Ar = C6H4NO2-4) and 16.5 [Ar = C6H3(NO2)2-2,4] kcal/mol. In 5-arylazo-1,2,3,4,5-pentamethylcyclopentadienes, 1,5-sigmatropic shifts of arylazo groups occur along the perimeter of the five-membered ring in conformers with the exo position of the azo group relative to the cyclopentadiene ring with significantly higher activation barriers: Δ E ≠ZPE, benzonitrile, 30.3 (Ar = C6H4NO2-4) and 27.5 [Ar = C6H3(NO2)2-2,4] kcal/mol. The calculations are in good agreement with the data for these compounds obtained by us earlier by dynamic NMR.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
