CO Assistance in ligand exchange of a ruthenium racemization catalyst: identification of an acyl intermediate
2009 (English)In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 131, no 27, 9500-9501 p.Article in journal (Refereed) Published
An acyl intermediate in the activation of eta(5)-(Ph(5)Cp)Ru(CO)(2)Cl by t-BuOK was identified by means of in situ FT-IR measurements and NMR spectroscopy. This strongly supports the conclusion that the ligand exchange takes place via CO assistance, i.e., that the activation occurs via nucleophilic attack by tert-butoxide on one of the CO ligands. The tert-butoxycarbonyl intermediate shows stretching vibrations at 1933 and 1596 cm(-1), corresponding to the CO and COOt-Bu groups, respectively. In the (13)C NMR spectrum, the CO group appears at 209.5 ppm and the COOt-Bu group at 208.7 ppm. The NMR assignments were confirmed by density functional theory calculations. The subsequent alcohol-alkoxide exchange is also thought to take place via CO assistance. However, no intermediate in that step could be detected.
Place, publisher, year, edition, pages
American Chemical Society , 2009. Vol. 131, no 27, 9500-9501 p.
IdentifiersURN: urn:nbn:se:su:diva-29966DOI: 10.1021/ja9038455ISI: 000268239400016OAI: oai:DiVA.org:su-29966DiVA: diva2:236580