Leaching from Heterogeneous Heck Catalysts:A Computational Approach

来源 :Chemical Research in Chinese Universities | 被引量 : 0次 | 上传用户:pengxianwei1986
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The possibility of carrying out a purely heterogeneous Heck reaction in practice without Pd leaching has been previously considered by a number of research groups but no general consent has yet arrived. Here, the reaction was, for the first time, evaluated by a simple computational approach. Modelling experiments were performed on one of the initial catalytic steps: phenyl halides attachment on Pd (111) to (100) and (111) to (111) ridges of a Pd crystal. Three surface structures of resulting were identified as possible reactive intermediates. Following potential energy minimisation calculations based on a universal force field, the relative stabilities of these surface species were then determined. Results showed the most stable species to be one in which a Pd ridge atom is removed from the Pd crystal structure, suggesting Pd leaching induced by phenyl halides is energetically favourable. The possibility of carrying out a purely heterogeneous Heck reaction in practice without Pd leaching has been previously considered by a number of research groups but no general consent has had arrived. Here, the reaction was, for the first time, evaluated by a simple computational approach . Modeling experiments were performed on one of the initial catalytic steps: phenyl halides attachment on Pd (111) to (100) and (111) to (111) ridges of a Pd crystal. Three surface structures of resulting were identified as possible reactive intermediates Following potential energy minimization calculations based on a universal force field, the relative stabilities of these surface species were then determined. induced by phenyl halides is energetically favourable.
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