ISSN:
1573-9171
Keywords:
nonamethylmetallocenecarbaldehydes
;
iron
;
ruthenium
;
osmium
;
molecular structure
;
intramolecular hydrogen bond
;
interionic hydrogen bond
;
O-protonation
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The products ofO-protonation of metallocenecarbaldehydes C5Me5MC5Me4CHO (M = Fe, Ru, Os) with HBF4 and CF3COOH were obtained for the first time, the adducts [C5Me5MC5Me4CH(OH)]+BF− being isolated in a pure state. The structures of the adducts depend on the nature of the metal and the anion and are governed by the correlation between their basicities. For example, the Fe-containing adducts have an open fulvenoid structure with an interionic hydrogen bond irrespective of the nature of the anion X (X = BF4 −, CF3COO−). In the case of the Ru- and Os-containing adducts in which the metal atoms are more basic than iron, the competition between the metal atom and the anion for the formation of a hydrogen bond with the OH group is clearly manifested in the IR and1H NMR spectra. In the presence of the weakly basic BF4 − anion, a cyclic structure with an intramolecular M...HO hydrogen bond is formed, while in the presence of a more basic F− or CF3COO− anion. it transforms to the open fulvenoid structure with an interionic hydrogen bond. The structures of the compounds obtained were determined by IR and1H NMR spectra, and the structure of the (C5Me5RuC5Me4CHOH)+...F− salt was proved by X-ray diffraction analysis.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00713612
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