129440-44-4Relevant articles and documents
Cyclometallation of polydentate ligands containing pyrazole groups, including the synthesis of platinum(IV) complexes with tripodal - ligand systems
Canty, Allan J.,Honeyman, Thomas R.
, p. 247 - 263 (1990)
Dimethylplatinum(II) complexes, PtR2(L), have been made by reaction of 2 with a range of polydentate nitrogen donor ligands containing one or more pyrazol-1-yl (pz) donor groups, including the new ligand bis(pyrazol-1-yl)(thien-2-yl)methane.The complexes give cis-PtMe2(py)2 when dissolved in pyridine at ambient temperature, except for PtMe2(L) (L = (pz)2CH2, (pz)2C(H)Ph, (pz)3CH, or (pz)2(mim)CH (mim = N-methylimidazol-2-yl)), which undergo cyclometallation at a C(5) position of one pyrazol-1-yl ring.The cyclometallated ligands have been examined as 'isoelectronic' analogues of nitrogen donor poly(pyrazol-1-yl)alkane and poly(pyrazol-1-yl)borate ligands.A carbon monoxide derivative, PtMe(CO) (1d) and a series of phosphine complexes have been prepared.The complex PtMe(py) (1a) and polymeric >n (2) undergo oxidative addition reactions with organohalides to give the platinum(IV) complexes (py)>X (7a-d) and fac-PtXMe(R) (8a-b), respectively.The new reagent 1-bromo-2-(pyrazol-1-yl)ethane forms (pzCH2CH2-N,C)>Br (10), containing both - and - ligands.Reaction of MeI or PhCH2Br with PtMe2> gives fac-PtXMe(R) (8a,b) directly, and PtMe2 undergoes a similar cyclometallation/oxidative addition in iodomethane to form fac-PtIMe2 (13).
