Our density functional theory study reveals that the dehydrogenation of ethanol catalyzed by an aliphatic PNP pincer Ru complex,(PNP)Ru(H)CO {1Ru,PNP = bis[2-(diisopropylphosphino)-ethyl]amino},and its Fe analogue,(PN...
Our density functional theory study reveals that the dehydrogenation of ethanol catalyzed by an aliphatic PNP pincer Ru complex,(PNP)Ru(H)CO {1Ru,PNP = bis[2-(diisopropylphosphino)-ethyl]amino},and its Fe analogue,(PNP)Fe(H)CO(1Fe),proceed via a self-promotion mechanism that features an ethanol molecule acting as a bridge to assist the transfer of a proton from ligand nitrogen to the metal center for the formation of *** calculated total free energy barrier of ethanol dehydrogenation catalyzed by 1Fe is only 22.1 kcal/mol,which is even 0.7 kcal/mol lower than the calculated total free energy barrier of the reaction catalyzed by 1Ru(Figure 1).Therefore,the potential of 1Fe as a low-cost and high-efficiency catalyst for the production of hydrogen from ethanol is promising.1 A recent experimental study of Beller and co-workers has confirmed 1Fe is an active catalyst for the dehydrogenation of methanol under mild condition.2 In addition to the finding of above self-promoted dehydrogenation mechanism for the aliphatic pincer complexes,the very different catalytic properties between the in ruthenium complexes with aromatic and aliphatic pincer ligands are analyzed based on our calculation results.
暂无评论