ISSN:
0894-3230
Keywords:
N-(aminoalkyl)-9-phenanthrenecarboxamides
;
molecular structures
;
folded conformations
;
Chemistry
;
Theoretical, Physical and Computational Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
---The molecular structures of three tertiary N-(aminoalkyl)-9-phenanthrenecarboxamides were investigated in solution and the solid state by means of 1H NMR spectroscopy and x-ray crystallography. The tertiary amides exist as a mixture of E and Z isomers in solution and the aminoalkyl groups exist as a mixture extended and folded conformers. A crystalline N-(aminoethyl)amide was obtained as the pure Z isomer in which the phenanthrene and amide planes are nearly perpendicular and the aminoethyl group is folded over the less hindered face of the amide group. Rotation about the Ar-C(O) bond is slow in resolution rendering these molecules chiral on the NMR time-scale. As a consequence, the α-methylene protons display large diasterotopic splittings when the aminoalkyl group is syn to the amide carbonyl. Folded conformations place the Z and E aminoalkyl groups in the deshielding and shielding regions, respectively, of the phenanthrene rings, resulting in large differences in chemical shifts. © 1997 John Wiley & Sons, Ltd.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
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