作者:Francesco Troisi、Carmine Gaeta、Teresa Pierro、Placido Neri
DOI:10.1016/j.tetlet.2009.06.110
日期:2009.9
Pyrrolamidocalix[4]arenes 1-4, members of a new class of anion receptors bearing pyrrolic units at the upper rim of calix[4]arene macrocycle, have been readily synthesized in good yields. Derivatives 1 and 3, with unsubstituted pyrrole units, Show a good selectivity for H2PO4 over F and AcO-, while the presence of electron-withdrawing NO2 substituents in 2 and 4 inverts the selectivity favoring more basic AcO- and F-. In addition, it is demonstrated that the flexibility of calix[4]arene skeleton, present in 1 but absent in 3, is very important in the fitting process that leads the amidopyrrole moieties to wrap the tetrahedral H2PO4- guest. (C) 2009 Elsevier Ltd. All rights reserved.