Multinuclear and dynamic NMR study of trans-[Pt(Cl)(PHCy2)2(PCy2)], [Pt(Cl)(PHCy2)3][BF4], [Pt(Cl)(PHCy2)3][Cl], trans-[Pt(Cl)(PHCy2)2[P(S)Cy(2)]], and trans-[Pt(Cl)(PHCy2)2[P(O)Cy2]]. Influence of intramolecular P=O...H-P and Cl...H-P interactions on restricted rotation about Pt-P bond. X-ray structure of trans-[Pt(Cl)(PHCy2)2[P(O)Cy2]].
Dynamic NMR experiments on trans-[Pt(Cl)(PHCy2)2[P(X)Cy2]]z where X is a lone pair (1, z = 0), H (2, z = +1), S (3, z = 0), or O (4, z = 0) show that the rotation around the P(X)-Pt bond is hindered for all molecules studied, with deltaG++ ranging from 8.2 to 11.0 kcal/mol. The highest value of the series was calculated for trans-[Pt(Cl)(PHCy2)2[P(O)Cy2]] (4) where intramolecular P=O...H-P interactions act as a molecular brake at room temperature. Single-crystal X-ray diffraction confirms the presence of both intra and intermolecular P=O...H interactions in solid 4. In the case of [Pt(Cl)(PHCy2)3]Cl, multinuclear NMR analysis indicates the presence of a P-H...Cl- interaction in aromatic or halogenated solvents which could have also a minor effect on the rotational barrier around the P(X)-Pt bond.
Mastrorilli
Piero
P
Dipartimento di Ingegneria delle Acque e di Chimica del Politecnico di Bari, via Orabona 4, I-70125 Bari, Italy. p.mastrorilli@poliba.it
Nobile
Cosimo F
CF
Latronico
Mario
M
Gallo
Vito
V
Englert
Ulli
U
Fanizzi
Francesco P
FP
Sciacovelli
Oronzo
O
D002412:Cations; D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D017671:Platinum Compounds / Q000737:chemistry*
D002412:Cations; D017671:Platinum Compounds