tailieunhanh - Quantum chemical study of reaction mechanism of [4+2]-cycloaddition between 2,3-dimethylbuta-1,3-diene and methyl acrylate

The quantum-chemical modeling mechanism of the [4+2]-cycloaddition reaction of 2,3 dimethylbuta-1,3-diene and methyl acrylate was conducted. Its qualitative aspects were analyzed at the molecular level by the program MOPAC2012 and semiempirical method RM1. | Quantum chemical study of reaction mechanism of 4 2 -cycloaddition between 2 3-dimethylbuta-1 3-diene and methyl acrylate Current Chemistry Letters 6 2017 1 6 Contents lists available at GrowingScience Current Chemistry Letters homepage Quantum chemical study of reaction mechanism of 4 2 -cycloaddition between 2 3-dimethylbuta-1 3-diene and methyl acrylate Yaroslav Kovalskyia Olga Marshalokb Natalia Vytrykusha and Halyna Marshalokc a Lviv Polytechnic National University. 12 Stepan Bandera Str. Lviv 79013 Ukraine b Danylo Halytsky Lviv National Medical University 69 Pekarska Str. Lviv 79010 Ukraine c Jan and Jedrzej Sniadecki University of Technology and Life Sciences in Bydgoszcz 85-225 Bydgoszcz Poland CHRONICLE ABSTRACT Article history The quantum-chemical modeling mechanism of the 4 2 -cycloaddition reaction of 2 3 Received August 21 2016 dimethylbuta-1 3-diene and methyl acrylate was conducted. Its qualitative aspects were Received in revised form analyzed at the molecular level by the program MOPAC2012 and semiempirical method RM1. October 24 2016 The potential energy surfaces of 2 3 dimethylbuta-1 3-diene and methyl acrylate 4 2 Accepted 10 November 2016 cycloaddition possible reaction pathways were constructed by restricted and unrestricted Available online Hartree-Fock approximation. It has been established that the molecule of the final product 10 November 2016 methyl-3 4-dimethylcyclohex-3-encarboxylate has the half-chair shape wherein the Keywords carboalkoxyl group is in the exo-orientation. Interaction between molecules of 2 3 Mechanism dimethylbuta-1 3-diene and methyl acrylate occurs by a two-step mechanism more likely than 4 2 -cycloaddition 2 3- one-step since the activation parameters of this interaction maximum coincide with the Dimethylbuta-1 3-diene experimental data. Methyl acrylate 2017 Growing Science Ltd. All rights reserved. 1. Introduction Mechanism of Diels-Alder reaction has been the subject of much interest and