Conformational Control of Calix[6]arenes Through Multiple Bridges

✍ Scribed by Hitos Galán; Javier de Mendoza; Pilar Prados

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 191 KB
• Volume: 2005
• Category: Article
• ISSN: 1434-193X
• DOI: 10.1002/ejoc.200500368

✦ Synopsis

Abstract

The synthesis of the A,D‐m‐xylylene‐bridged B,C,E,F‐tetra‐O‐alkylcalix[6]arenes 1b–c and the A,D‐B,C;E,F‐triply bridged calix[6]arenes 2a–c is described. The cone conformation of the new bridged calix[6]arenes has been established by a full set of 1D/2D ^1^H and ^13^C NMR techniques. These compounds are substantially more rigid than calix[6]arene analogues with an A,D‐p‐xylylene bridge, and the resulting cavities are better defined. Molecular mechanics optimization of triply bridged calix[6]arenes 2b and 2c resulted in structures fully consistent with the NMR spectra. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)