Chemical Selection and Self-Assembly in a Cyclization Reaction

✍ Scribed by Dr. Dmitry M. Rudkevich; Prof. Julius Rebek Jr.

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 376 KB
• Volume: 36
• Category: Article
• ISSN: 0044-8249
• DOI: 10.1002/anie.199708461

✦ Synopsis

PMB = 4-MeOC6H4CHz 2: R = 4-MeC6H4

New chemical behaviors frequently emerge at the interface between noncovalently bound molecules, and self-assembly is one means of uncovering such phenomena.['] For example, reversible encapsulation of small molecules can be observed in hydrogen-bonded, self-complementary dimers; the encapsulation process is governed by unusual thermodynamic parameters.I2I Here we present evidence that even the synthesis of these capsules can involve molecular recognition.

The system consists of a cyclization reaction on a template, H. R , H 1. tBUOK, BrCH2C(O)OEt, DMSO, 54% -0 2. CAN, MeCN-HzO, 4:1, 60% 2. K2C03, MeOH-H,O, 5:1.90-95% but differs from the many such reactions of, say, crown ether or _.