Dimethyl ether, ruthenium complex

Ruthenium complexes B also undergo fast reaction with terminal alkenes, but only slow or no reaction with internal alkenes. Sterically demanding olefins such as, e.g., 3,3-dimethyl-l-butene, or conjugated or cumulated dienes cannot be metathesized with complexes B. These catalysts generally have a higher tendency to form cyclic oligomers from dienes than do molybdenum-based catalysts. With enol ethers and enamines irreversible formation of catalytically inactive complexes occurs [582] (see Section 2.1.9). Isomerization of allyl ethers to enol ethers has been observed with complexes B [582]. 

The vinyl derivative 4-methyl-4 -vinyl-bpy is valuable for chemical electrode modification because its ruthenium and osmium complexes can be polymerized to generate electroactive films with variable properties.86 This unsymmetric ligand was prepared in 35% overall yield from 4,4 -dimethyl bipyridine by first lithiating one methyl group and quenching the anion with (chloromethyl)methyl ether, then reacting with potassium t-butoxide to effect elimination.87,88... 

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