A DFT Study of Stannane Dehydrocoupling Catalyzed by Cp₂LaH

Citations Over TimeTop 19% of 2006 papers

Abstract

All the pathways leading to bis-stannane and regeneration of the catalyst Cp2LaH (Cp = η5-C5H5) for the stannane SnH4 have been computed using the DFT (B3PW91) method. In all cases, the reaction is at least a two-step process with a common first step, which is the Sn−H activation of the stannane, leading to the hydrostannyl complex Cp2LaSnH3. From a pure thermodynamic point of view, the overall process is found to be exergonic by 9.3 kcal·mol-1. Since the most stable product of the energy profile is the intermediary hydrostannyl complex, the second step, which corresponds to Sn−Sn coupling, is endergonic. This explains the relatively low turnover, found experimentally, for the homocoupling of stannane into bis-stannane. This overall process is in agreement with the experiment made on hafnium complexes, where the intermediary hydrostannyl compounds have been isolated and characterized. From a kinetic point of view, the second reaction step is proposed to occur through a direct SnH3 transfer of the hydrostannyl to the incoming stannane rather than stannylene or stannylenoide insertion into the incoming stannane.

Related Papers

• → On the nature of organic and inorganic centers that bifurcate electrons, coupling exergonic and endergonic oxidation–reduction reactions(2018)37 cited
• → The synthesis and the properties of monohalogeno derivatives of stannane(1971)12 cited
• → Chemistry of stannane(1970)
• → ChemInform Abstract: Synthesis and Properties of Trimethyl(trifluorosilyl)stannane.(1989)
• → ChemInform Abstract: Application of Free Radical Substitution Reaction into Interconversion of 1‐Alkenyl Sulfides, 1‐Alkenylgermanes, and 1‐Alkenylstannanes.(1988)