UV, IR and NMR spectral analyses reveal that 2,6-naphthoquinone forms a 1:1 host-guest type of complex with 5,11,17,23,29,35-hexa-tert-butyl-37,38,39,40,41, 42-hexahydroxycalix(6)arene while 1,4-naphthoquinone does not do so at low concentrations (1 x 10AM). 1,4-Benzoquinone forms a 2:1 molecular complex with 5,11,17,23-tetra-tertbutyl- 25,26,27,28-tetrahydroxycalix(4)arene and 5,11,17,23,29,35-hexa-tert-butyl-37,38,39,
40,41,42-hexahydroxycalix(6)arene but no complexation has been observed with 5,11,17,23,
29,35,41,47-octa-tert-butyl- 50,51,52,53,54,55,56-octahydroxycalix(8)arene under similar
conditions. 9,10-Anthraquinone, 1,2-dihydroxy-9,10-anthraquinone and 1,2,5,8-tetrahydroxy-
9,10-anthraquinone, show no interaction with p-tert-butyl-calix(n)arenes (n = 4, 6, 8).
Studies carried out indicate that 2,6-naphthoquinone can be recognised by 1,17,23,29,35
-hexa-tert-butyl-37,38,39,40,41,42- exahydroxycalix(6)arene even when present in a mixture of quinones and other related compounds.