Christopher M. Haar

Synthetic and thermochemical studies of reactions of the 16-electron ruthenium complex [(Ph2PNMeNMePPh2)2RuCl]BF4 with H2, CH3CN and CO

Abstract The 16-electron ruthenium complex [(Ph2PNMeNMePPh2)2RuCl]BF4 (2) has been prepared by chloride abstraction from (Ph2PNMeNMePPh2)2RuCl2 (1) with AgBF4. The enthalpies of reaction of [(Ph2PNMeNMePPh2)2RuCl]BF4 (2) with H2, CH3CN and CO, leading to the formation of complexes [(Ph2PNMeNMePPh2)2RuCl(L)]BF4 (L=H2 (3); CH3CN, (4); CO (5)), have been measured by anaerobic calorimetry in CH2Cl2 at 30°C. These reactions are rapid and quantitative. The relative order of stability established for these complexes is 5>4>3. Reactivity and thermochemistry of one alkyne, HCCnBu, has also been investigated.

Solution thermochemical study of ligand substitution reactions of hybrid alkyl/fluoroalkoxy phosphorus ligands in the L2Fe(CO)3 system

Abstract The enthalpies of reaction of (BDA)Fe(CO) 3 (BDA=(C 6 H 5 )CHCHC(O)CH 3 , benzylideneacetone) with a series of novel fluorinated phosphine ligands, PR 2 OR f (R=Ph, i Pr, Cy; R f =(CH 2 ) 2 (CF 2 ) 5 CF 3 ) and (R f O) 2 PCH 2 CH 2 P(OR f ) 2 (dOR f pe), leading to the formation of L 2 Fe(CO) 3 complexes (L=PR 2 OR f ) have been measured by solution calorimetry in THF at 50°C. Remarkably, reaction enthalpies are essentially invariant over this series of ligands, despite the differing steric and electronic properties of the phosphorus ligands. Carbonyl stretching frequencies help in the estimation of useful electronic parameters associated with the novel phosphorus ligand series.