Abstract
The calix[4]pyrrole is reported as a novel organocatalyst for regioselective ringopening of epoxides under mild reaction conditions. The reaction involves elemental halogen as a nucleophile to afford vicinal halohydrins in good to excellent yield (75-95%). The reactivity of the halide ion in the reaction is governed by different factors, including solvent polarity, temperature and non-covalent interactions of the functional group present on calix[4]pyrrole moiety with halide ions. An efficient methodology has been developed for the regioselective synthesis of halohydrins in good to excellent yields.
Keywords: Calixpyrrole, epoxides, halohydrins, elemental halogen, organocatalysis, regioselective.
Graphical Abstract
[http://dx.doi.org/10.2174/157017911795529137]
(b) Lee, M.; Lamb, J.R.; Sanford, M.J.; LaPointe, A.M.; Coates, G.W. Chem. Commun. (Camb.), 2018, 54, 12998-13001.
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