Oxidative addition reactions of Rh(SbPh3)3(CO)X (X=Cl, Br) with organic phenyl-substituted propargyl compounds. Rhodium(III) phenylpropargyl products and their conversion to rhodiacyclic complexes

Reactions of Rh(SbPh3)3(CO)X (X=Cl (1), Br (2)) with PhCCCH2Y (Y=OTs, Cl, Br) in CH2Cl2 at ambient temperature lead to formation of the oxidative addition products Rh(SbPh3)2(CO)X(Y)(η1-CH2CCPh) (X=Cl, Y=OTs (3), Cl (4), Br (5); X=Br, Y=OTs (6), Br (7)). Complexes 3 and 6 each react with pyridine at room temperature to afford the rhodiacyclopent-3-ene-2-ones Rh(SbPh3)2(py)X(η2-C(O)C(Ph)C(OTs)CH2) (X=Cl (8), Br (9)). Treatment with AgOTs converts 8 to Rh(SbPh3)2(py)(OTs)(η2-C(O)C(Ph)C(OTs)CH2) (10). Addition of AgOTf (or AgBF4) and then immediately an excess of PhCCCH2Br to a CH2Cl2 solution of 1 at ambient temperature affords an orange solid that is formulated tentatively as [Rh(SbPh3)2(CO)Cl(η3-CH2CCPh)]OTf (or BF4) (11a and 11b). All new complexes were characterized by a combination of elemental analysis, FAB mass spectrometry, IR and NMR (1H and 13C{1H}) spectroscopy and conductance measurements.