Displacement Kinetics of η<sup>2</sup>-Bound Furan and 2,3-Dihydrofuran from Mn and Cr Centers: Evidence for the Partial Dearomatization of the Furan Ligand
作者:Jeremy R. Andreatta、G. Benjamin Cieslinski、Madeeha Batool、Xue-Zhong Sun、Michael W. George、Edward N. Brothers、Donald J. Darensbourg、Ashfaq A. Bengali
DOI:10.1021/ic900724f
日期:2009.8.17
The displacement of eta(2)-coordinated ligands from the photolytically generated CpMn(CO)(2)L and BzCr(CO)(2)L [Cp = eta(5)-C5H5, Bz = eta(6)-C6H6, L =2,3-dihydrofuran (DHF), furan] complexes by pyridine has been studied. The displacement reactions span a wide range of time scales from microseconds to hours and were studied using a range of time-resolved IR spectroscopic techniques. The substitution reactions follow a dissociative pathway and the measured activation enthalpies provide an estimate for the strength of the metal-(eta(2)-furan) and metal-(eta(2)-DHF) interactions. In these complexes, the Cr center binds both ligands weaker than the Mn center, There is a similar to 6-10 kcal/mol difference in the binding enthalpies of eta(2)-furan and eta(2)-DHF to both metals suggesting that this difference is the result of a partial loss of resonance energy in the case of the aromatic furan ligand upon interaction with the metal.
KALININ, V. N.;DERUNOV, V. V.;LUSENKOVA, M. A.;PETROVSKY, P. V.;KOLOBOVA,+, J. ORGANOMET. CHEM., 379,(1989) N, C. 303-309
作者:KALININ, V. N.、DERUNOV, V. V.、LUSENKOVA, M. A.、PETROVSKY, P. V.、KOLOBOVA,+
DOI:——
日期:——
Reactions of vinylidene and allenylidene cymantrene derivatives with isonitriles