ISSN:
0887-624X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The synthesis of N,N-diethyl-9-carbazolylacetamide (6), (R,S)- and (R)-N,N-diethyl-2-(9-carbazolyl)propanamide (7), N,N′-dimethyl-N,N′-di-(9-carbazolylacetyl)-1,2-ethanediamine (11), and (R)-N,N′-dimethyl-N,N′-di[2-(9-carbazolyl)propanoyl]-1,2-ethanediamine (13) is reported. The racemic compound, (R,S)-2-(9-carbazolyl)propanoic acid (2), was resolved by partial crystallization of the diastereomeric salts formed between 2 and (+)-α-methylbenzylamine. The 1H-NMR spectra of 6 and 7 showed magnetic nonequivalence of the chemically equivalent protons of the methyl and methylene groups in 6 and 7 due to partial double bond character of the amide bond. The upfield resonances corresponding to the two sets of methyl and methylene protons were assigned by the aromatic solvent-induced shift (ASIS) method to the protons anti to the carbonyl oxygen in the conformation of amide bond in 6 and 7. The 1H-NMR spectra of 11 and (R)-13 were used to determine the population of anti-anti, anti-syn (syn-anti) and syn-syn conformers in the structures of these dimer model compounds; the relative conformer populations were 0.45:0.47:0.08 and 0.28±0.02:0.29±0.01:0.43±0.01 in 11 and (R)-13.
Additional Material:
6 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pola.1986.080240310
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