10.1021/om9807001.s001
Christopher M. Haar
Christopher M.
Haar
Steven P. Nolan
Steven P.
Nolan
William J. Marshall
William J.
Marshall
Kenneth G. Moloy
Kenneth G.
Moloy
Alfred Prock
Alfred
Prock
Warren P. Giering
Warren P.
Giering
Synthetic, Structural, and Solution Thermochemical
Studies in the Dimethylbis(phosphine)platinum(II)
System. Dichotomy between Structural and
Thermodynamic Trends
American Chemical Society
1999
phosphine size
enthalpic stability scale
reaction enthalpy
unidentate phosphines
Solution Thermochemical Studies
cone angles
Structural
phosphine ligands
PEt 3
cone angle
31 P NMR data
PMe 2 Ph
P 2 PtMe 2
PCy 3
Thermodynamic Trends Reaction enthalpies
solution calorimetry
P 2 PtMe 2 complexes
1999-01-16 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Synthetic_Structural_and_Solution_Thermochemical_Studies_in_the_Dimethylbis_phosphine_platinum_II_System_Dichotomy_between_Structural_and_Thermodynamic_Trends/3783372
Reaction enthalpies of the complex (COD)PtMe<sub>2</sub> (COD = η<sup>4</sup>-1,5-cyclooctadiene) with an
extensive series of unidentate phosphines have been measured by solution calorimetry. The
molecular structures of <i>cis</i>-P<sub>2</sub>PtMe<sub>2</sub> for P = PEt<sub>3</sub>, PMe<sub>2</sub>Ph, P(pyrrolyl)<sub>3</sub>, and PCy<sub>3</sub> have been
determined by single-crystal X-ray diffraction. The relative stabilities of the resulting P<sub>2</sub>PtMe<sub>2</sub> complexes are strongly influenced by the size (cone angle) of the incoming phosphine,
with larger cone angles resulting in less thermodynamically stable complexes. Crystallographic and <sup>31</sup>P NMR data, however, do not reflect the enthalpic stability scale and are
more closely correlated to the electronic (χ) character of the phosphine ligands. The strength
of the Pt−P interaction, as determined from these structural data, is greatest for phosphines
with electron-withdrawing substituents, regardless of phosphine size or reaction enthalpy.