CALIX(N)ARENE-QUINONE INTERACTIONS - MOLECULAR RECOGNITION OF 2,6-NAPHTHOQUINONE BY T-BUTYL-37,38,39,40,41,42-HEXAHYDROXYCALIX(6)ARENE

UV, IR and NMR spectral analyses reveal that 2,6-naphthoquinone forms a 1:1 host-guest type of complex with t-butyl-37,38,39,40,41,42-hexahy droxycalix(6)arene while 1,4-naphthoquinone does not do so at low conc entrations (1 x 10(-4)M). 1,4-Benzoquinone forms a 2:1 molecular compl ex with a-tert-butyl-25,26,27,28-tetrahydroxycalix(4)arene and t-butyl -37,38,39,40,41,42-hexahydroxycalix(6)arene but no complexation has be en observed with 5,11,17,23, l-49,50,51,52,53,54,55,56-octahydroxycali x(8)arene under similar conditions. 9,10-Anthraquinone, 1,2-dihydroxy- 9,10-anthraquinone and 1,2,5,8-tetrahydroxy-9,10-anthraquinone, show n o interaction with p-tert-butyl-calix(n)arenes (n = 4, 6, 8). Studies carried out indicate that 2,6-naphthoquinone can be recognised by t-bu tyl-37,38,39,40,41,42-hexahydroxycalix(6)arene even when present in a mixture of quinones and other related compounds.