Synthesis, characterisation and X-ray diffraction studies of new lower rim calix[4]arene derivatives containing mixed donor atoms

Abstract

New lower rim p-tert-butylcalix[4]arene derivatives containing tetrathiophene functional groups as well as derivatives with two different pendant arms alternately arranged, one of which is in all cases a methylsulfanyl substituent whilst the other is either a tertiary amine (aliphatic of alicyclic) or a methylthiophene or an amide substituent, have been synthesised and characterised by 1H and 13C NMR spectroscopy in chloroform at 298 K. The use of phase transfer catalysis in the synthesis of calixarene derivatives is discussed. X-Ray diffraction studies of 5,11,17,23-tetrakis-(1,1-dimethylethyl)-25,26,27,28-tetrakis-[2-(thienyl)methoxy]calix[4]arene 1a and 5,11,17,23-tetrakis-(1,1-dimethylethyl)-25,27-bis[(2-methylsulfanyl)ethoxy]-26,28-bis[2-(diethylamino)ethoxy]calix[4]arene 2b are reported.