We showed earlier [1] that calix [4]arenes containing a sulfamide moiety with NH protons on the "upper rim" and four ethoxycarbonyl groups on the "lower rim" can exhibit the properties of a heteroditopic receptor, i.e., they can simultaneously chelate cations and anions. In this paper, by reacting tetrakis(azidosulfonyl)calixarene 1 with N-cyclohexylcyanoacetamide in the presence of a catalytic amount of sodium ethoxide, we obtained tetrakis(5-amino-1,2,3-triazol-1-ylsulfonyl)calixarene 2, which when boiled with excess triethylamine undergoes a Dimroth rearrangement to form tetrakis[(1H-1,2,3-triazol-5-yl)aminosulfonyl]calixarenes 3 (Scheme 1).We used the membrane transport method to study the chelating properties of the synthesized compounds [1]. In a study of transport through a liquid impregnated membrane, we showed that the initial sodium sulfate flux for compound 2 was 1.37·10 -6 ; for 3, 6.95·10 -5 ; for 5-tosylamino-1,2,3-triazole-4-(N-cyclohexyl)carboxamide, 7.50·10 -10 mol·sec -1 ·m -2 . The cooperative heteroditopic effect compared with compound 1, which can chelate only cations, was 1.9 and 95 respectively for compounds 2 and 3.Thus we have shown that calixarene 2 (containing a triazole ring with an unsubstituted amino group at the 5 position of the heterocycle) weakly chelates anions while calixarene 3 (containing an isomeric triazole ring with a sulfamoyl group) exhibits the properties of a ditopic receptor.The 1 H NMR spectra were taken on a Bruker DRX-400 (400 MHz) in CDCl 3 , internal standard TMS.
25,26,27,28-Tetrakis(ethoxycarbonylmethoxy)-5,11,17,23-tetrakis(1-(5-amino-4-N-cyclohexylcarbamoyl-1,2,3-triazol-1-yl)sulfonyl)calix[4]arene (2).A suspension of calix[4]arene 1 (119 mg, 0.1 mmol) and cyclohexyl cyanoacetamide (66 mg, 0.4 mmol) in alcohol (7 ml) was stirred for 15 h at 40°C; the precipitate was filtered out and crystallized from alcohol. Yield 0.1 g (60%); mp 249°C. 1 H NMR spectrum, δ, ppm (J, Hz): 7.58 (8H, s, ArH); 6.55 (8H, br. s, NH 2 ); 5.19 (4H, d, J = 13.7, CHAr); 4.88 (8H, s, OCH 2 ); 3.80 (8H, t, J = 4.1, OCH 2 ); 3.50 (4H, d, J = 13.7, CHAr); 3.34-3.38 (4H, m, CH); 1.2-2.2 (40H, m, C 6 H 10 ); 1.13 (12H, t, J = 4.1, CH 3 ). Found, %: N 15.29. C 80 H 100 N 20 O 24 S 4 . Calculated, %: N 15.11.
25,26,27,28-Tetrakis(ethoxycarbonylmethoxy)-5,11,17,23-tetrakis-(N-(4-N-cyclohexylcarbamoyl-1H-1,2,3-triazol-4-yl)sulfamoyl)calix[4]arene (3).A solution of calix[4]arene 2 (93 mg, 0.05 mmol) in ethanol (30 ml) and triethylamine (5 ml) was boiled for 3 h, the solvent was evaporated, and the residue was crystallized from ethanol. Yield 88%; mp 217°C (decomposes). 1 H NMR spectrum, δ, ppm (J, Hz): 8.00 (1H, br. s, NH); 7.50 (8H, s, ArH); 6.86 (4H, s, NH); 5.13 (4H, d, J = 13.7, CHAr); 4.88 (8H, s, OCH 2 ); 3.80 (8H, t, J = 4.1, OCH 2 ); 3.56 (4H, d, J = 13.7, CHAr); 3.34-3.38 (4H, m, CH); 1.2-2.2 (40H, m, CH); 1.12 (12H, t, J = 4.1, CH 3 ).