EFFECT OF THE LIGAND L ON THE TRANSESTERIFICATION PROCESSES OF BISMETHOXYCARBONYL IRON COMPLEXES - CIS FE(CO2ME)(2)(CO)(3)L, L = CO, PME3, PPH3, P(OET)(3)

Citation
M. Sellin et al., EFFECT OF THE LIGAND L ON THE TRANSESTERIFICATION PROCESSES OF BISMETHOXYCARBONYL IRON COMPLEXES - CIS FE(CO2ME)(2)(CO)(3)L, L = CO, PME3, PPH3, P(OET)(3), Journal of organometallic chemistry, 562(2), 1998, pp. 183-189
Citations number
22
Categorie Soggetti
Chemistry Inorganic & Nuclear","Chemistry Inorganic & Nuclear
ISSN journal
0022328X
Volume
562
Issue
2
Year of publication
1998
Pages
183 - 189
Database
ISI
SICI code
0022-328X(1998)562:2<183:EOTLLO>2.0.ZU;2-E
Abstract
The synthesis of the new mer or fac Fe(CO2Me)(2)(CO)(3) (L) (L = PMe3: 2a; L = PPh3: 2b; L = P(Cy)(3): 2c; L = P(OEt)(3): 2d) complexes of v arious electron densities has been realized in order to study the tran sesterification reactions between these methoxycarbonyl complexes and alcohols. The easy formation of [Fe(CO2Me)(CO)(4)(L)] [BF4] by removin g a methoxy group from these complexes clearly indicates that their me thoxy group and particularly the one trans to the phosphane ligand are mobile. However whereas the unsubstituted complex Fe(CO2Me)(2)(CO)(4) (1) presents fast exchange reactions with ethanol, 2a and 2b are foun d unreactive towards the same reagent and 2d (L = P(OEt)(3)) only unde rgoes slow transesterification reactions at 28 degrees C. It is propos ed an associative mechanism for this transesterification process proba bly induced by a preliminary nucleophilic addition of an alcohol molec ule at a terminal carbonyl ligand prior to the elimination of the meth oxy group of a methoxycarbonyl. (C) 1998 Elsevier Science S.A. All rig hts reserved.