クリプトンズとパラクワットに基づいた最初のシドオロタキサン型 [3]複合体:自己組み立てと結晶構造
Feihe Huang1, Harry W Gibson, William S Bryant
1Department of Chemistry, Virginia Polytechnic Institute & State University, Blacksburg, Virginia 24061, USA.
Journal of the American Chemical Society
|August 2, 2003
まとめ
新型クリプトン分子 (3a) が合成され,溶液とガス相でのパラクアットと1:1複合体を形成した. しかし,固体分析は 2:1 ステキオメトリーを示し,変数の宿主-ゲスト複合比を示した.
科学分野:
- 超分子化学 超分子化学
- オーガニック・シンセシス オーガニック・シンセシス
- ホスト・ゲスト・ケミストリー
背景:
- クリプトンドは,ゲストを結合する能力で知られているマクロサイクル化合物です.
- ホスト・ゲストステキオメトリーの理解は,分子認識システムの設計に不可欠です.
研究 の 目的:
- 新しいクリプトン,ビス (1,3,5-フェニレン) トリ (1,4,7,10-テトラオキサデシル) (3a) を合成する.
- 新しい暗号のホスト・ゲストステキオメトリーをパラクワットで調査する.
- cryptandシステムにおける複雑なステキオメトリーに影響を与える要因を探求する.
主な方法:
- 偽高希釈条件を使用したcryptand3aの合成.
- アソシエーション定数測定を用いた溶液中の複合性研究.
- ガス相ステキオメトリー測定のための質量スペクトロメトリー.
- 固体構造分析のためのX線結晶学.
主要な成果:
- Cryptand 3aは良好な収量で合成されました.
- アセトン溶液とガス相で1:1の宿主-ゲスト複合ステキオメトリが観察されました.
- 固体X線結晶学では,3aの複合体と,パラクワットと関連する暗号 (3b) の2:1ステキオメトリが示されました.
- ゲスト分子は,固体状態の2つの暗号と分子の空洞を部分的に占めていることが判明しました.
結論:
- この研究は,クリプトンベースの複合体において,同じホスト-ゲストペアに対して異なるステキオメトリが起こる可能性があることを初めて示しています.
- ステキオメトリーの観察された変動は,相 (溶液,ガス,または固体) に依存しています.
- これらの発見は,調節可能な性質を持つ超分子組成物の設計に意味を持っています.
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