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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

DFT perspective on the selectivity and mechanism of ligand-free Heck reaction involving allylic esters and arenediazonium salts

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Author(s):
Menezes da Silva, Vitor H. [1, 2] ; Morgon, Nelson H. [3] ; Correia, Carlos R. D. [2] ; Braga, Ataualpa A. C. [1]
Total Authors: 4
Affiliation:
[1] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Ave Prof Lineu Prestes 748, BR-05508000 Sao Paulo - Brazil
[2] Univ Estadual Campinas, Inst Quim, Dept Quim Organ, CP 6154, BR-13083970 Campinas, SP - Brazil
[3] Univ Estadual Campinas, Inst Quim, Dept Fis Quim, CP 6154, BR-13083970 Campinas, SP - Brazil
Total Affiliations: 3
Document type: Journal article
Source: JOURNAL OF ORGANOMETALLIC CHEMISTRY; v. 896, p. 5-15, SEP 15 2019.
Web of Science Citations: 1
Abstract

A density functional theory (DFT) study has been carried out with respect to the cationic and neutral mechanism of ligand-free Heck-Matsuda cross-coupling reaction involving allylic esters and arenediazonium salts. Full Heck-Matsuda (HM) catalytic cycles were explored in the presence of different possible combinations of ligands based on previous mass-spectrometry studies. DFT calculations were performed to examine the olefinic substrate influences on the regioselectivity of this ligand-free Heck reaction. A multi-step mechanism was revealed for the oxidative addition of palladium (0) center to carbon-nitrogen bond of arenediazonium cation. The cationic migratory insertion pathway is favored by a chelated coordination involving the palladium center and the allylic ester. In contrast, for neutral complexes, a bidentate coordination of acetate ligand is the favored pathway. Regarding the hydride elimination step, the resulting free energy profile is quite flat, revealing that the Heck product and the hydride complex are easily formed for both cationic and neutral cycles. The reductive elimination step assisted by acetate is a very exothermic process, going through small relative reaction barriers. These results constitute new insights to a better understanding of the selectivity and the mechanism of ligand-free Heck-Matsuda reactions. (c) 2019 Elsevier B.V. All rights reserved. (AU)

FAPESP's process: 11/07895-8 - Theoretical study of the Heck-Matsuda reactions
Grantee:Ataualpa Albert Carmo Braga
Support Opportunities: Scholarships in Brazil - Post-Doctorate
FAPESP's process: 17/18207-1 - Evaluating new palladium chiral catalysts and application in enantioselective Heck-Matsuda reaction development in new olefinic models: computational studies
Grantee:Vitor Hugo Menezes da Silva
Support Opportunities: Scholarships in Brazil - Post-Doctorate
FAPESP's process: 14/25770-6 - New frontiers in cross-coupling reactions promoted by palladium: combining enantioselective catalysis, C-H activations, new materials and in flux reactions aiming at high efficiency and sustainability in synthetic processes
Grantee:Carlos Roque Duarte Correia
Support Opportunities: Research Projects - Thematic Grants
FAPESP's process: 15/01491-3 - Theoretical study of cross-coupling reactions: homogeneous and heterogeneous catalysis
Grantee:Ataualpa Albert Carmo Braga
Support Opportunities: Regular Research Grants
FAPESP's process: 13/04813-6 - Mechanistic studies of Heck-Matsuda reactions: a theoretical investigation
Grantee:Vitor Hugo Menezes da Silva
Support Opportunities: Scholarships in Brazil - Doctorate