Selenium ligands substitution reactions

The reaction of alkyl selenols occurs normally to give selenium-substituted carbene complexes in low yield (Fischer et al., 1973c). However, reaction of the more acidic selenophenol with carbene complexes leads to cleavage of the carbene ligand. Apparently, the carbon-metal bond in the tetravalent intermediate is protonated by CgHjSeH. 

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