Synthesis and reactivity of new trimethylplatinum(IV) complexes containing chiral Schiff bases as ligands: Crystal structure of (OC-6-44-C)-[PtIMe3{κ2-(R)-Ph2P(C6H4)CHNC*H(Ph)Me-P,N}]

NMR Studies of Optically Active Schiff Bases

“…The platinum(II) complexes of the amino acid Schiff bases have been studied by 1 H NMR by Offiong et al 105 Comparison of the 1 H chemical shifts between ligands and complexes has revealed the trans-geometry of the complexes and engagement of the azomethine group in bonding to the metal ion. Ramirez et al 106 have investigated the series of platinum complexes of chiral Schiff bases [43]. [43] The proton signals have displayed long-range couplings with phosphorus and platinum atoms.…”

Cyclometallated platinum(II) complexes containing the chiral ligand [2-(diphenyl-phosphanyl)-benzylidene]-(1-phenyl-ethyl)-amine: Synthesis and molecular structures of the compounds [PtCl(Me){κ2-(R)-Ph2P(C6H4)CHNCH(Ph)Me-P,N}] and [Pt{κ3-(S)-Ph2P(C6H4)CHNCH(C6H4)Me-P,N,C}Py]BF4

“…Reagent grade solvents were dried, distilled, and stored under a nitrogen atmosphere. The starting complex [PtIMe 3 ] 4 [19], the ligands (S)-and (R)-Ph 2 PC 6 H 4 CH@NCH(Ph)Me [20] and diastereomeric mixtures of the complex [PtIMe 3 {j 2 -Ph 2 P(C 6 H 4 )CH@NCH(Ph)Me-P,N}] (1) [18] were synthesized according to literature procedures. 1 H, 31 P{ 1 H} and 13 C{ 1 H} NMR spectra were recorded on a Bruker AC-200P and Avance-400 spectrometers.…”

“…Treatment of diastereomeric mixtures of [PtIMe 3 {j 2 -Ph 2 P(C 6 H 4 )CH@NCH(Ph)Me-P,N}] (Sc-1) [18] with silver tetrafluoroborate followed by addition of thioanisol gives rise to a mixture of complexes 2 and 3 (Scheme 1). Formation of compounds 2 and 3 from Sc-1 implies a common step involving the reductive elimination of ethane and iodide abstraction but, while complex 2 retains the remaining Me-Pt group (d Me = 0.26 ppm, 2 J HPt = 69.1 Hz, 3 J HP = 3.3 Hz), complex 3 can be described as the result of a further elimination of methane accompanied by an orthometallation reaction.…”

“…We recently reported the preparation of the related complexes 7 and 8, following a similar route, but using pyridine 7 or triphenylphosphine 8 as ancillary ligands (Scheme 2) [18]. It has been proposed the solvate 6 as a common intermediate for the formation of both types of products [18].…”

“…However, when pyridine (Py) was used instead of PPh 3 only the reductive elimination step occurred and [PtMe(Py){j 2 -Ph 2 P(C 6 H 4 )CH@ NCH(Ph)Me-P,N}][BF 4 ] was the product obtained [18].…”