Smith JN, Ennis C, Lucas NT. Rigid, biconical hydrogen-bonded dimers that strongly encapsulate cationic guests in solution and the solid state.
Chem Sci 2021;
12:11858-11863. [PMID:
34659726 PMCID:
PMC8442710 DOI:
10.1039/d1sc01802g]
[Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 08/04/2021] [Indexed: 11/24/2022] Open
Abstract
The octol of a new rigid, tetraarylene-bridged cavitand was investigated for self-assembly behaviour in solution. 1H and DOSY NMR spectroscopic experiments show that the cavitand readily dimerizes through an unusual seam of interdigitated hydrogen-bonds that is resistant to disruption by polar co-solvents. The well-defined cavity encapsulates small cationic guests, but not their neutral counterparts, restricting the conformation of sequestered tetraethylammonium in solution and the solid state.
A robust, dimeric capsule forms quantitatively in low-polarity solvents via a seam of 8 hydrogen bonds. The resulting electron-rich cavity selectively binds small organic cations over neutral counterparts.![]()
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