Computational studies of Brønsted acid-catalyzed transannular cycloadditions of cycloalkenone hydrazones

Manuel Pedrón; Jana Sendra; Irene Ginés; Tomás Tejero; Jose L Vicario; Pedro Merino

doi:10.3762/bjoc.19.37

Computational studies of Brønsted acid-catalyzed transannular cycloadditions of cycloalkenone hydrazones

Beilstein J Org Chem. 2023 Apr 20:19:477-486. doi: 10.3762/bjoc.19.37. eCollection 2023.

Authors

Manuel Pedrón¹, Jana Sendra², Irene Ginés¹, Tomás Tejero³, Jose L Vicario², Pedro Merino¹

Affiliations

¹ Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, 50009 Zaragoza, Spain.
² Departamento de Química Orgánica e Inorgánica, Universidad del País Vasco (UPV/EHU) P.O. Box 644, 48080 Bilbao, Spain.
³ Instituto de Síntesis Química y Catálisis Homogénea (SQCH), Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain.

Abstract

The contribution to the energy barrier of a series of tethers in transannular cycloadditions of cycloalkenes with hydrazones has been computationally studied by using DFT. The Houk's distortion model has been employed to evaluate the influence of the tether in the cycloaddition reaction. That model has been extended to determine the contribution of each tether and, more importantly, the effect exerted between them. In addition to the distortion induced by the tethers, the entropy effects caused by them has also been studied. The analysis of the evolution of the electron localization function along the reaction revealed the highly concerted character of the reaction.

Keywords: DFT; distortion model; hydrazones; transannular cycloadditions.

Grants and funding

This research was supported by the Spanish AEI (PID2019-104090RB-100, FEDER-CTQ2016-76155-R, FEDER-PID2020-118422GB-I00 and FPI fellowship to J. S.), Basque Government (Grupos IT908-16), and Government of Aragón (Grupos Consolidados, E34_20R and a pre-doctoral contract to M. P.).