6533b82afe1ef96bd128cb0b

RESEARCH PRODUCT

Cyclometallation reactions in complexes of the type Rh(oq)(CO)(P(o-BrC6F4)Ph2)

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Abstract The reaction of Rh(oq)(CO)(PCBr) (PCBr = P(o-BrC6F4)Ph2; oq = 8-oxyquinolinte)_ in refluxing toluene in the presence of Et4NBr (1/4 molar ratio) gives Rh(oq)Br(PC) (H2O), PC = P (o-C6F4)Ph2, in practically quantitative yield. The water molecule is readily displaced by various P-donor ligands to give complexes of general formula Rh(oq)Br(PC) PR3 (PR3 = PPh3, P(p-MeC6H4)3, P(p-MeOC6H4)3, P(p-FC6H4)3, P(PMe)3 and P(OPh3). The molecular structure of the compound Rh(oq)Br(PC) (PPh3) has been determined by X-ray methods. Crystals of the title compound are monoclinic, space group P21/n with unit cell dimensions a 11.273(4), b 20.087(8), c 17.471(7) A and β 102.15(8)°. The final R for 2304 diffractometer data refined by least-squared is 0.0468. The compound has a distorted octahedral coordination with the phosphorus atoms in a cis disposition. The RhP bond lengths are significantly different. The P atom of the metallated phosphine, which is trans to N, has a RhP distance of 2.308(4) A, while the PPh3, which is trans to C, has a RhP distance of 2.422(4) A. The most distorted angles around the rhodium atom are P(1)Rh-P(2) 104.7(1)° and P(1)RhC(1) 69.2(3)°.