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.