Abstract
A series of dihalobis(tertiary phosphine)nickel(II) complexes, NiL2X2, has been synthesized. The tertiary phosphine ligands include PR3, PR2Ph3 and PRPh2 types where R is cyclopropyl or cyclohexyl and Ph is phenyl. These tertiary phosphines and several others Were selected to test the relative importance of steric and electronic effects on the planar-tetrahedral structural equilibrium exhibited by NiL2X2 type complexes. The thermodynamics and kinetics of this interconversion Were determined by proton magnetic resonance and magnetic suscepttbility measurements in dichloro-methane solution. Results show that steric factors are relatively unimportant in affecting the thermodynamics of the structural equilibrium. Electronic effects, however, are extremely important and are interpreted via a metal-phosphorus π-bonding scheme. Kinetic parameters were measured by standard pmr line shape techniques and are reported for trialkyl- and dialkylphenylphosphine complexes for the first time. The activation parameters are similar to other NiL2X2 complexes where L = alkyldiphenylphosphine.
Original language | English (US) |
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Pages (from-to) | 156-163 |
Number of pages | 8 |
Journal | Inorganic chemistry |
Volume | 12 |
Issue number | 1 |
DOIs | |
State | Published - Jan 1 1973 |