Calixarene-based molecular capsule

✍ Scribed by Takashi Arimura; Satoshi Matsumoto; Osamu Teshima; Takeshi Nagasaki; Seiji Shinkai

• Book ID: 104225835
• Publisher: Elsevier Science
• Year: 1991
• Tongue: French
• Weight: 144 KB
• Volume: 32
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)93441-5

✦ Synopsis

calix [6]arene.

The capsule is capable of "constrictive binding" of a guest molecule (N-methylformanillde).

Calixarenes are [ln]metacyclophanes wlth a half-bowl-shaped architecture. This architecture tempted us to design a mld-air capsule from two calixarenes by the binding of two upper rims through "adhesive" functional groups.

The similar idea has been reported by Cram et al.: they used cyclic resorcinol tetramers as half-bowl building-blocks for the synthesis of "carcerands". 1-3 Calixarenes have, on the other hand, the isomeric spectrum from tetramer to octamer. This suggests the possibility of the synthesis of calixarene-based "carcerands" with a different mid-air size which cannot be achieved by the use of cyclic resorcinol tetramers. Firstly, we attempted the synthesis of a "carcerand" from a callx[6]arene bearing six sulfonate groups on the upper rim and a callx[6]arene bearing six trimethylammonlomethyl groups on the upper rim. 4 Although the product (polylon complex) could include several guest molecules, the characterization was extremely difficult because of its poor solubility."

We thus changed the direction toward the synthesis of a soluble callxrene-based "carcerand".