The Mechanism and Origin of Enantioselectivity in the Rhodium-Catalyzed Asymmetric Ring-Opening Reactions of Oxabicyclic Alkenes with Organoboronic Acids: A DFT Investigation

Abstract

The mechanism and origins of enantio-and stereoselectivity in the asymmetric ring-opening (ARO) reactions of oxabicyclic alkenes with organoboronic acids catalyzed by rhodium/Josiphos has been examined at the B3LYP/defTZVP level of theory. The mechanism consists of four steps including transmetalation, carborhodation, β-oxygen elimination, and hydrolysis. Energetic discrimination in the chirality-imparting step arises from attractive C−H−π interactions between the transmetalated aryl group and the Josiphos ligand, as well as steric clashes between the Josiphos ligand and the oxabicyclic alkene. Computational results indicate that the rate-determining step is involved in the hydrolysis of the rhodium(I) alkoxide from the ring-opened intermediate. In the overall catalytic cycle, the greatest free energy barrier is 23.4 kcal/mol, which supports that the Rh-catalyzed ARO reactions take place at mild reaction conditions, which is consistent with experimental observations.

Silver Dependent Enantiodivergent Gold(I) Catalysed Asymmetric Intramolecular Hydroamination of Alkenes: A Theoretical Study

“…Functional PBE has been frequently employed [104,105], as it provides acceptable results for transition metal complexes. Moreover, the high-quality def-TZVP basis set that we have employed in the present work has previously been used to study several systems [106]. Furthermore, though it is always desirable to further increase predictive accuracy of computational studies, it consistently results in increased computational cost.…”

Expanding horizons in conceptual density functional theory: Novel ensembles and descriptors to decipher reactivity patterns

“…5,6 Over the last decades, based on firm mathematical and physical grounds, CDFT has thus notably provided many relevant tools to rationalize and predict chemical reactions through the use of descriptors that can be, in general, derived from the principles of quantum mechanics. [7][8][9] They have found applications in almost all chemistry fields, such as organic chemistry, [10][11][12] organometallics, 13,14 catalysis 15,16 and material science. 17,18 In the CDFT framework, usual quantum reactivity descriptors generally correspond to first and second order derivatives in the CDFT framework.…”

“…F I G U R E 2 Aldehyde and additional ketones[9][10][11] subseries of electrophiles.F I G U R E 3The six nitrogencontaining nucleophiles [compounds[12][13][14][15][16][17] with their respective experimental nucleophilicity.2…”

Estudo computacional das reações de borilação de substratos insaturados catalisadas por Ag e Cu

“…Apesar do amplo sucesso do uso da teoria do funcional de densidade para cálculos que envolvem mecanismos de reações, [179][180][181] a análise de desempenho de seus variados funcionais provou ser uma etapa fundamental a ser executada. 182 Recentemente, Silva et al 182 avaliaram a seletividade do acoplamento de Heck usando diferentes funcionais, e provaram através desse estudo que funcionais corrigidos com os efeitos de dispersão são necessários para descrever corretamente a regiosseletividade da reação de Heck.…”