Stoichiometric Activity of Well-Defined, Metal Alkylidenes with Alkanes

22 Stoichiometric Activity of Well-Defined, Metal Alkylidenes with Alkanes 

The alkane metathesis with the W-alkyhdyne/alkyl complexes supported on alumina or sihca-alumina yielded a different distribution of branched, neopentyl alkane derivatives, albeit in lower amounts. These results suggest a different mechanism than the alkyhdene-supported metal complexes depicted above. A chrect, C - H bond activation of propane on the alkyhdyne species [91,92] or, alternatively, the formation of bisalkylidene intermediates [93] have been proposed [71]. 

The metathesis of cyclic alkanes using this catalyst was studied, where it was found to be able to convert cyclooctane (COA) into a distribution of cyclic (from Cj to Cy) and macrocyclic alkanes with the formula (from C 2 to C ) 

Alkane Metathesis by Tandem, Dual-Catalytic Systems 

In this section, the tandem system comprising of two catalysts for the alkane metathesis reaction will be discussed one catalyst for the dehydrogena-tion/hydrogenation steps and another one for the olefin metathesis step. In contrast to the multifunctional, single-catalyst systems, there are only a few reports that describe tandem, dual-catalyst systems for the alkane metathesis reaction [100]. Herein, the Chevron system will be discussed [8], followed by the recent development of another dual-catalytic system developed by Goldman and Brookhart [18]. 

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