PLATINUM(II) COMPLEXES: INFRARED SPECTRA IN THE 300–800 CM⁻¹ REGION

Abstract

Bands have been assigned to stretching frequencies of bonds between platinumand chlorine, nitrogen and oxygen which are observed in the far infrared region. The positions of these bands have been related to the structures of several complexes. Iiuproved procedures are given for the preparation of complexes of the type I< [P~CIJL] and trans-PtCI?L(arn), where L is an unsaturated organic ligand and a m is an aromatic amine.As part of a study of the trans effect of unsaturated organic ligands in chloro-complexes of bivalent platinum, the infrared spectra of a series of such conlpounds have been examined in the 300-800 cin-I region. Variations in the stretching frequencies, v Pt-C1, have been investigated and assignments made for the platinum -aromatic nitrogen stretching modes, v Pt-N. From the spectrum of bis(acety1acetono) platinum(I1) stretching frequencies v Pt-0 have been determined. RESULTS AND DISCUSSION (a) Chloro-complexesIn Table I where L is an unsaturated organic ligand. Since the coinplex ion is essentially square planar, with the platinuin atom a t the center, we expect to find two platinum-chlorine stretching frequencies: (a) the asyinmetric stretching vibration of the linear C1-Pt-C1 unit (the syinilletric vibration being inactive in the infrared); and (b) the stretching frequency of the platinum-chlorine group trans to the ligand L. This latter frequency should be lower than the first because of the weakening of the bond by the high trans effect of the unsaturated ligand (1) as reported by Adams and Chatt (2) for the propene platinous chloride ion. We find that the stretching frequency of the trans chlorine (306-314 cnl-I) is some 20 cm-I lower than that of the Cl-Pt-C1 unit (325-340 cin-I), which is in accordance with expectations. For the ally1 alcohol complex the band a t 305 cm-I is rather weak and may be affectedIPresent address:

UV‐Induced Synthesis and Stabilization of Surfactant‐Free Colloidal Pt Nanoparticles with Controlled Particle Size in Ethylene Glycol

“…IR absorption spectra of platinum nanoparticle synthesis mixtures prepared using different NaOH concentrations in Figure B show concurrent results. Previous publications regarding experimental and theoretical calculations on IR absorption spectra of various platinum salts and its derivatives claim that almost all the absorption bands related to platinum atoms appear below 400 cm −1 and hence are not visible here in this range. However, organic compounds that play a role in the reaction mechanism and NP stabilization might be observable using IR.…”

Synthesis of complexes of the type cis-Pt(amine) (unsaturated ligand)Cl2 and crystal structure cis-Pt(methylaimne) (dimethylhexynediol)Cl2

“…Trans compounds containing pyridine derivatives and unsaturated ligands have been known for a long time (2,8,9). Compounds of the type K[Pt(un)C13] have been reported (8,(10)(11)(12) and their reactions with pyridine derivatives (py) give trans-Pt(py)(un)C12 because of the large trans effect of alkenes and alkynes.…”

“…Compounds of the type K[Pt(un)C13] have been reported (8,(10)(11)(12) and their reactions with pyridine derivatives (py) give trans-Pt(py)(un)C12 because of the large trans effect of alkenes and alkynes. Much of the work reported on alkynes has been done with bulky ligands like (CH3)3C-C=C4(CH3)3 and glycols of the type R 2 C ( O H ) -C 4 ( O H ) R 2 since ligands like R m -H do not form stable Pt(I1) T complexes.…”

Halogen-bridged complexes of platinum(II) and their reactions with dimethylformamide

“…tmns-[Pt(acetylene)(L)Cl,] was used and the rate of reaction was increased. However, only the bridged compound with pyridine has been prepared (2). The second method is the decomposition of acids:…”