1998 Fiscal Year Final Research Report Summary
Study on Synthesis of New Crystalline Host of Cycloadducts, Function and Crystal Structure
| Project/Area Number |
09672148
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
Chemical pharmacy
|
|---|
| Research Institution | Kumamoto University |
|---|
Principal Investigator |
HARANO Kazunobu Kumamoto University, Pharmaceutical Sciences, Professor, 薬学部, 教授 (30037593)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
ETO Masashi Kumamoto University, Pharmaceutical Sciences, Assistant, 薬学部, 助手 (70221116)
MATSUOKA Toshikazu Kumamoto University, Pharmaceutical Sciences, Assistant Professor, 薬学部, 助教授 (50150545)
|
|---|
| Project Period (FY) |
1997 – 1998
|
| Keywords | Diels-Alder adduct / crystalline host / phencyclone / N-naphthylmaleimide / DSC / TG / X-ray analysis / inclusion complex |
|---|
| Research Abstract |
Crystalline inclusion compounds between simple organic molecules are useful models for studying weak interatomic interactions in molecular recognition and self-organization of molecules. In the course of studies of the pericyclic reaction behavior of cyclopentadienones toward various unsaturated compounds, we observed that the Diels-Alder (DA) adduct of phencyclone and p-bromostyrene or cyclooctatetraene forms a crystalline inclusion complex with recrystallization solvents (host : benzene : MeOH=1 : 1 : 1).
In this project, a series of crystalline host compounds, which have a bicyclo[2.2.1] heptene-7-one system, has been synthesized and their inclusion behavior has been investigated using nuclear magnetic resonance spectroscopy, single crystal X-ray analysis, differential scanning calorimetry (DSC) and thermogravimetry (TG). For example, the cycloadduct la of phencyclone and N-naphthylmaleimide forms a 1 : 1 crystalline inclusion complex with 2-butanone. The X-ray analysis indicates tha
… More
t the plane of the naphthalene ring is almost perpendicular to the maleimide ring and is covered with the phenanthrene ring in an 'edge-to-face' manner (T-shaped conformation). The crystal packing diagram indicates the presence of weak lattice forces supported by C-H・pi and C-H・O interactions. The DSC of la butanone showed a broad endothermic pattern corresponding to the guest loss at 136ﾟC, followed by an endothermic peak at 272ﾟC caused by melting of the host. The TG curve supported the host : guest stoichiometry derived from the crystal structure. The total weight loss was observed to be 10.6% in agreement with the expected loss of 10.8 % for a 1 : 1 ratio. In conclusion, T-shaped interaction between the naphthalene and phenanthrene rings plays a leading role in the solid-state inclusion complex formation. The inclusion mode of other solvents by the N-arylmaleimide adducts was also investigated. Similar inclusion behavior toward aromatic solvents has been observed in several DA adducts. The crystal structures were determined by the X-ray analysis. Less
|
