Stoichoimetric amount

Homo-coupling of vinylic mercurials occurs readily under palladium195 or rhodium196 catalysis, but with the stoichoimetric amount of a reagent (equation 111)195. Divinylpal-ladium intermediates may be involved in this reaction. This reaction is also of limited synthetic scope since organomercurials are usually prepared via vinylboranes, which... 

As neutral species, the adducts 11-EtjO are very labile and are quantitatively dissociated in C6D6 at 25°C. The presence of stoichoimetric amounts of ether does therefore not suppress catalytic activity. This is in stark contrast to [Cp2ZrMe]+ where EtjO is held strongly and is a potent catalyst poison. 

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