1992 Fiscal Year Final Research Report Summary
1,3-INTERACTION BETWEEN AMIDE NITROGENS------Possibility and Limitation
| Project/Area Number |
02640384
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| Research Category |
Grant-in-Aid for General Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Research Field |
有機化学一般
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| Research Institution | THE UNIVERSITY OF TOKYO |
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Principal Investigator |
TAKEUCHI Yoshito Department of Chemistry, College of Arts & Sciences, The University of Tokyo, Professor, 教養学部, 教授 (80012384)
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| Co-Investigator(Kenkyū-buntansha) |
YOSHIMURA Shin Department of Chemistry, College of Arts & Sciences, The University of Tokyo, As, 教養学部, 助手 (20182818)
OGAWA Keiichiro Department of Chemistry, College of Arts & Sciences, The University of Tokyo, As, 教養学部, 助教授 (50114426)
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| Project Period (FY) |
1990 – 1992
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| Keywords | Amide-type nitrogen / 1,3-Interaction / Amine-type nitrogen / Variable temperature NMR / X-ray crystallographic analysis / Restricted rotation of amides / Nitrogen inversion |
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| Research Abstract |
The purpose of this investigation is to explore the possible 1,3- interaction between amide-type nitrogen atoms. It seems that 1,3,5- tribenzoylperhydro-1,3,5-triazine(A) is the most appropriate system for this purpose.
The X-ray crystallographic analysis of (A) revealed that the molecule is symmetric and the nitrogen atoms have approximate trigonal structures. This means that the nitrogen involved is a conventional amide nitrogen, which is in contrast to the tetrahedral nitrogen in 1,2-diacylhydrazine. The results were already published in Acta Cryst.
Though no indication of 1,3-interaction between amide nitrogens, we explored variable temperature of C-13 NMR spectra of (A). As the temperature lowered, there was observed a change of line-shape which corresponds to the amide rotation. As the temperature further lowered, there was observed the second chemical exchange. This rate process is most likely due to the nitrogen inversion. Unfortunately the NMR spectrometer in general cannot reach temperature below-100C and hence we failed to finalize our interpretation.
In conclusion, it is likely that in (A) the nitrogen atoms have a tetrahedral character to some extent. This might mean that the 1,3-interaction between amide nitrogens do exist. Further study would be required to finalize this conclusion.;C and hence we failed to finalize our interpretation.
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