Co Select Insert Theoretical Study Of The Oxidation Reactions And Silylene

Density functional theory (DFT) calculations at the B3LYP level of theory are carried out of study and analyze the following two projects. Our major purpose is to investigation the molecular structures, bonding, and mechanisms of the two following reaction systems.1. The CO migratory insertion into M-O and M-C bonds of the new model (PH3)2M(η2-CH2CH2O) (M= Ni, Pd and Pt) (model (d)) proposed in this work has been studied using density functional calculations. It is found (1) when M= Ni, CO migratory insertion into Ni-C is kinetically and thermodynamically favored, and (2) when M= Pd and Pt, the insertion into M-O bond is preferred via a one-step process. Further investigation on CO migratory insertion using Pt(PMe3)2(C7H10O) (R) derived from the experimental compound Pt(PEt3)2(C7H10O) gives the same conclusions as model (d) with M= Pt. Results obtained from the reaction of model (d) (M= Pt) with CO are consistent with the experimental observation that CO prefers to insert into Pt-O bond of Pt(PEt3)2(C7H10O). The reaction is predicted to proceed through a one-step process rather than a dissociative process.2. In 2009, Hashimoto and coworkers reported the synthesis and properties of a silyl(silylene)ruthenium complex, together with the exploration on the facile replacement of the methyl groups with alkoxy groups of a silyl ligand. In their originally proposed mechanism, the reductive elimination processes were proposed to occur in the early and middle stages of the reaction. Clearly, this would lead to the end of reaction by coordination of isonitrile and would not lead to the final product. In this paper, we proposed an alternative mechanism in which isonitrile coordinates to the metal center unless all the alkoxylation processes are completed. The structural characteristic for all the intermediates involved in the alkoxylation processes is that all of them have 18e configurations and the interactions between metal center and silicon areσ-or (σ+π)-bonded. The methoxy-bridged bis(silylene) ruthenium complexes are found to be important intermediates in the course of this reaction.