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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.)

Heck arylation of acyclic olefins employing arenediazonium salts and chiral N,N ligands: new mechanistic insights from quantum-chemical calculations

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Menezes da Silva, Vitor H. [1] ; Oliveira, Caio C. [1] ; Correia, Carlos Roque D. [1] ; Braga, Ataualpa A. C. [2]
Total Authors: 4
[1] Univ Estadual Campinas, Inst Quim, Dept Quim Organ, CP 6154, BR-13083970 Campinas, SP - Brazil
[2] Univ Sao Paulo, Inst Quim, Dept Quim Fundamental, Ave Prof Lineu Prestes 748, Sao Paulo, SP - Brazil
Total Affiliations: 2
Document type: Journal article
Source: THEORETICAL CHEMISTRY ACCOUNTS; v. 139, n. 4 APR 4 2020.
Web of Science Citations: 0

A quantum-chemical study based on the Kohn-Sham density functional theory (DFT) has been performed in order to investigate the asymmetric Heck-Matsuda (HM) reactions involving a chiral N,N ligand pyrimidine-oxazoline. The oxidative addition (OA) of arenediazonium cation was analyzed to provide further insights in the unexpected high reactivity of N,N-ligated palladium(0)-based catalysts observed in these HM processes. DFT calculations suggest that the ionogenic nature of metal center promoted by the arenediazonium cation addition increases the electronic reactivity of palladium(0) toward the donor N,N ligand. The concerted and multi-step mechanisms were computed for the OA step, in which the cationic aryl-palladium(II) complex formation was revealed as the thermodynamic driving force for this process. The importance of conformational analyses was highlighted, particularly when an acyclic alkenol olefin is taken as substrate, since its absence could lead to misleading predictions about the selectivity of these HM systems. While the enantioselectivity is controlled by the combination of steric and dispersion interactions between ligand and substrate, the regioselectivity is mostly oriented by the electronic nature of olefinic carbons. DFT predictions on the selectivity were shown to be in quantitative agreement with experimental results. (AU)

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: 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-Doctoral
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