| Abstract: | Calix6]pyrrole 2 and the "hybrid systems" calix3]furan3]pyrrole 12, calix2]furan4]pyrrole 13, and calix1]furan5]pyrrole 14, have been synthesized by increasing conversion of the furan units present in the readily accessible calix6]furan 3 to pyrroles. The host-guest chemistry of these novel macrocycles towards a number of anions, including halogen ions, dihydrogen phosphate, hydrogen sulfate, nitrate, and cyanide has been investigated in solution by (1)H NMR titration techniques and/or phase transfer experiments. The solid-state structures of the free receptors 2, 12, and 13, the 1:1 complexes of calix6]pyrrole 2 with chloride and bromide, and the 1:1 complex of 14 with chloride are also reported. |
