<i>m</i>-Diethynylbenzene Macrocycles: Syntheses and Self-Association Behavior in Solution
作者:Yoshito Tobe、Naoto Utsumi、Kazuya Kawabata、Atsushi Nagano、Kiyomi Adachi、Shunji Araki、Motohiro Sonoda、Keiji Hirose、Koichiro Naemura
DOI:10.1021/ja012458m
日期:2002.5.1
synthesized and their self-association behaviors in solution were investigated. Cyclic tetramers, hexamers, and octamers of DBMs having exo-annular octyl, hexadecyl, and 3,6,9-trioxadecyl ester groups were prepared by intermolecular oxidative coupling of dimer units or intramolecular cyclization of the corresponding open-chain oligomers. The aggregation properties were investigated by two methods, the (1)H
已经合成了间二乙炔基苯大环 (DBM),buta-1,3-diyne-bridged [4(n)]metacyclophanes,并研究了它们在溶液中的自缔合行为。通过二聚体单元的分子间氧化偶联或相应开链低聚物的分子内环化制备具有外环辛基、十六烷基和3,6,9-三氧杂十二烷基酯基团的DBM的环状四聚体、六聚体和八聚体。聚集特性通过两种方法进行研究,(1) H NMR 光谱和蒸气压渗透压法 (VPO)。尽管从两种方法获得的关联常数之间观察到一些差异,但定性观点彼此一致。VPO 自聚集分析揭示了 DBM 在丙酮和甲苯中的独特聚集行为,NMR 方法未阐明。即,无限缔合的缔合常数比二聚化常数大几倍,表明二聚体的形成(成核机制)增强了聚集。在极性溶剂中,由于大环骨架和溶剂之间的疏溶剂相互作用,DBMs 的聚集比在氯仿中更强。此外,与氯仿相比,DBM 在甲苯和邻二甲苯等芳香族溶剂中更容易自缔合。特别是,具有大大环空腔的六聚