Meta-Bridged calix[4]arenes: a straightforward synthesis via organomercurial chemistry
Flídrová K;1 Slavík P;1 Václav Eigner;2 Hana Dvořáková;3 Pavel Lhoták1*
1Ústav organické chemie, 2Ústav chemie pevných látek. 3Centrální laboratoře, Vysoká škola chemicko-technologická v Praze, Technická 5, 166 28 Praha 6
Chem. Commun. 2013, 49, 6749 – 6751 IF=6.378
An unprecedented regioselectivity of the mercuration reaction leading to the meta-substituted calix[4]arenes represents a novel type of substitution in classical calixarene chemistry. As this substitution pattern has not been accessible so far, it paves the way for the synthesis of unusual calixarene derivatives. Starting from meta-mercurated calix[4]arene the Pd-catalysed bridging of two neighbour phenolic units enabled the preparation of systems where themetapositions of the calixarene skeleton are intramolecularly bridged via additional single bond. Palladium-catalysed C-H activation thus leads to completely novel type of calix[4]arenes unknown in the literature. Highly distorted and rigid cavities of these compounds can be attractive for many applications in supramolecular chemistry as the complexation ability and/or conformational behaviour of parent macrocycles are substantially amended. The novel methodology represents very straightforward approach to a unique substitution pattern in calixarene chemistry with potential applications in the design of novel calixarene-based receptors (including inherently chiral systems).
The whole work including design, synthesis, structure elucidation and characterization of new compounds was done in the Institute of Chemical Technology, Prague.