Computational Study of the Extensive Role of Heterocyclic Ligands in Acetylene Hydration by a Bifunctional Organometallic Catalyst

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• 作者：Amy J. Arita ; Janet Cantada ; Douglas B. Grotjahn ; Andrew L. Cooksy
• 刊名：Organometallics
• 出版年：2013
• 出版时间：December 9, 2013
• 年：2013
• 卷：32
• 期：23
• 页码：6867-6870
• 全文大小：278K
• 年卷期：v.32,no.23(December 9, 2013)
• ISSN：1520-6041

文摘

A computational model based on density functional calculations is presented for the hydration of acetylene to form acetaldehyde on the organotransition-metal fragment CpRu(PMeb>2b>Im鈥?b>2b>⁺ (where Me = methyl and Im鈥?= 1,4-dimethylimidazol-2-yl). The predicted 10-step reaction mechanism features extensive participation of the basic imidazolyl nitrogens in three distinct hydrogen transfer steps which stabilize the reaction pathway through a series of hydrogen donor鈥揳cceptor exchanges. Because several equivalents of water are present in the experiments, the impact of solvation on the activation barriers of all ten steps has been estimated by a combination of explicit solvent and semiempirical continuum methods. The results are in qualitative agreement with intermediates observed in laboratory studies of similar catalysts, forming the basis for a complete investigation of the mechanism.