Cyclometallation reactions

Technetium and Rhenium

“…Typical nitrogen-containing metallocyclic compounds are illustrated in structures (78a), 465 (78b) 467 and (82). 470 intermediate complexes, as is also the case in the metallation of o-tolylphosphine by [Re2(CO)io]. 468 In this reaction the methyl group is metallated to give a five-membered ring in preference to metallation on the aromatic ring (which would give a four-membered metallocycle in the product).…”

Bis(azobenzenido)dicarbonylosmium(II)

“…1) nigan, Knox & Pauson, 1969). Related Os complexes with (CHaNCHC6H4-) (Choo Yin & Deeming, 1977) and benzo[h]quinoline (Bruce, Goodall & Stone, 1973) as the ligands have also been prepared from Os3(CO)l 2. Two coordinated azobenzenido ligands have also been observed in the structure of bis(azobenzenido)-rhodium acetate (Craik, Knox, Pauson, Hoare & Mills, 1971).…”

Cyclopalladate Complexes of 4-Methoxy-N- {(E)-(piperidin-1-yl) phenyl) Methylene} Aniline: Synthesis, Spectral Characterization and Biological Evaluation

“…The 1 H NMR spectrum of complex (1) showed the presence of a broadened unresolved pattern in the aromatic region which can explain the folded openbook shape structure of the complex. The folded structure of the acetate bridged complexes caused signals of the aromatic protons to be broadened, probably due to the anisotropic effect of the ring currents.…”

“…Since the first cyclometallated complex was synthesized, the cyclometallation process has become an important part of organometallic chemistry (1)(2)(3) , especially for the preparation of complexes derived from Schiff bases which are known to undergo facile cyclometallation as nitrogen donors. These cyclometallated complexes are formed when an organic ligand is linked to the metal ion center -C bond and an additional bonding of the metal ion via an appropriate donor atom to complete the stability more often than five membered metallated rings.…”

“…These cyclometallated complexes are formed when an organic ligand is linked to the metal ion center -C bond and an additional bonding of the metal ion via an appropriate donor atom to complete the stability more often than five membered metallated rings. Also, the cyclometallation reactions were one of the first known examples of C-H bond activation and cyclometallated complexes of a wide variety of ligands containing N, O,P or S as a hetero-atom have been described (1)(2)(3) .…”