Acta Scientific Pharmaceutical Sciences (ASPS)(ISSN: 2581-5423)

Research Article Volume 7 Issue 6

Theoretical Investigation of Pd-catalyzed Carbo-aminative Annulation of 1,6-enyne with 2-Iodoaniline Via 6-Endo-Trig Mode

Nan Lu*, Chengxia Miao and Xiaozheng Lan

College of Chemistry and Material Science, Shandong Agricultural University, Taian City, P.R. China

*Corresponding Author: Nan Lu, College of Chemistry and Material Science, Shandong Agricultural University, Taian City, P.R. China.

Received: March 13, 2023; Published: May 24, 2023


The mechanism is investigated for Pd-catalyzed carbo-aminative cyclization of 1,6-enyne with 2-iodoaniline. The regioselective addition of Pd-inserted 2-iodoaniline across alkyne and intermolecular insertion of olefin leads to alkyne-to-alkene adducts. After olefin isomerization, a pallado intermediate is obtained upon aza-conjugate addition. The β-hydride is eliminated with the help of Pd. The oxidative aromatization promoted by carbonate ion makes the oxidation level consistent with desired product. The regioselectivity of 6-endo-trig cyclization is determined through the superiority over other two modes in Heck-type intramolecular coupling. The promotion of active Pd(0) lies in the barrier decrease of rate-limiting olefin isomerization and aza-conjugate addition especially the β-hydride elimination. These results are supported by Multiwfn analysis on FMO of specific TSs and MBO value of vital bonding, breaking.

 Keywords: Annulation; 1,6-enynes; Regioselectivity; 6-endo-trig; Aryl Palladation


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Citation: Nan Lu., et al. “Theoretical Investigation of Pd-catalyzed Carbo-aminative Annulation of 1,6-enyne with 2-Iodoaniline Via 6-Endo-Trig Mode". Acta Scientific Pharmaceutical Sciences 7.6 (2023): 37-47.


Copyright: © 2023 Nan Lu., et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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