H. Werner et al., GENERATION OF GAMMA-FUNCTIONALIZED ALKYNYL LIGANDS BY MIGRATORY INSERTION OF AN ALLENYLIDENE UNIT INTO A M-OR BOND, Chemical communications, (12), 1996, pp. 1413-1414
The hydroxyrhodium(I) complexes 2a,b, which are prepared from the corr
esponding chloro derivatives 1a,b and KOBu(t), react with acetic acid
and phenol at room temperature to give the new acetato and phenolate m
etal compounds 3a,b and 4a,b almost quantitatively; subsequent treatme
nt of 3a,b and 4a,b with CO leads to migratory insertion of the alleny
lidene unit into the Rh-OR bond to yield gamma-functionalized alkynyl
ligands.