Rational design of model Pd(ii)-catalysts for C-H activation involving ligands with charge-shift bonding
Dongxia Ma1, Congjie Zhang1, Zhe-Ning Chen2
1Key Laboratory of Macromolecular Science of Shaanxi Province, School of Chemistry & Chemical Engineering, Shaanxi Normal University, Xi'an, 710062, China. zcjwh@snnu.edu.cn.
Abstract:
In this work, five new palladium(ii) complexes have been designed as the model catalysts for methane to methyl trifluoroacetate conversion. All these compounds are analogues of the well-established (bis-NHC)PdBr2 complex (NHC, N-heterocyclic carbenes), derived by complexing the palladium(ii) metal ion with the derivatives of bis-2-borabicyclo[1.1.0]but-1(3)-ene (bis-2BB) ligands using the sp2 carbons. Our density functional theory calculation results suggest that the (bis-2BB)PdBr2 catalysts outperform the popular (bis-NHC)PdBr2 complex in the desired catalytic process, and further reveal that the charge-shift bonding in the bis-2BB ligands contributes to the improved catalytic performance. These findings may spark new ideas for experimental design of more efficient organometallic catalysts for C-H bond activation and functionalization.
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