ISSN:
0030-4921
Keywords:
Chemistry
;
Analytical Chemistry and Spectroscopy
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
13C magnetic resonance spectra of several enamino ketones with secondary and tertiary amino groups were obtained for trifluoroacetic acid solutions. In both series O-protonation is predominant and the chemical shifts are related to the electron density changes with respect to the parent base. The spectra of the tertiary compounds are interpreted in terms of slow rotation around the C-1—C-2 and C-3—N bonds discernible at room temperature. O-protonated forms of the secondary enamino ketones undergo further reaction on C-2 yielding pyridinium salts. The mechanism of formation of the quaternary salts is interpreted and the additivity parameters of the 13C n.m.r. chemical shifts in the pyridinium ions is briefly discussed.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/mrc.1270090705