SYNTHESIS, CHARACTERIZATION AND X-RAY-DIFFRACTION STUDIES OF NEW LOWER RIM CALIX[4]ARENE DERIVATIVES CONTAINING MIXED-DONOR ATOMS

New lower rim p-tert-butylcalix[4]arene derivatives containing tetrath iophene functional groups as well as derivatives with two different pe ndant arms alternately arranged, one of which is in all cases a methyl sulfanyl substituent whilst the other is either a tertiary amine (ali phatic of alicyclic) or a methylthiophene or an amide substituent, hav e been synthesised and characterised by H-1 and C-13 NMR spectroscopy in chloroform at 298 K. The use of phase transfer catalysis in the syn thesis of calixarene derivatives is discussed. X-Ray diffraction studi es of rakis-(1,1-dimethylethyl)-25,26,27,28-tetrakis-[2- (thienyl)meth oxy]calix[4]arene 1a and xy]-26,28-bis[2-(diethylamino)ethoxy]calix[4] arene 2b are reported.