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Indian Journal of Chemistry -Section B (IJC-B) >
IJC-B Vol.46B [2007] >
IJC-B Vol.46B(09) [September 2007] >
| Title: | Rotational equilibria in boat conformations of N-acyl-r-2,c-6-di(2-hetero- aryl)piperidin-4-ones using NMR spectra and semiempirical MO calculations |
| Authors: | Thenmozhiyal, J C
Venkatraj, M
Ponnuswamy, S
Jeyaraman, R |
| Keywords: | N-acyl-r-2
c-6-di(2-heteroaryl)piperidin-4-one
NMR spectra
Semiempirical MO calculation
Boat conformation
N-acetyl
N-benzoyl
N-phenylcarbamoyl |
| Issue Date: | Sep-2007 |
| Publisher: | CSIR |
| Abstract: | Four N-acyl-r-2,c-6-di(2-heteroaryl)piperidin-4-ones 3-6 have been prepared and their conformational preferences examined using ¹H and ¹³C NMR spectral studies and semiempirical MO calculations. Solution state conformational studies on the compounds 3-6 by ¹H and ¹³C NMR spectral methods indicated the preference for the boat conformation with coplanar orientation of N-acyl groups. The energy barrier for N-C rotation in 3 has been found to be 58.4 kJ mol⁻¹ using variable temperature ¹H NMR spectral studies. The semiempirical MO calculations, using AM1 method, also suggested the preference of boat conformation for the N-acyl derivatives 3-6. |
| Page(s): | 1526-1536 |
| ISSN: | 0376-4699 |
| Source: | IJC-B Vol.46B(09) [September 2007]
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