| Abstract
| - A comparative study of the binding of nitrate and sulfate with two macrocycles of different dimensionality derived from isophthalaldehyde, a monocycle, L1, derived from a Schiff base condensation with dien (diethylenetriamine) and its corollary bicycle, L2, obtained from a similar condensation with tren (2,2‘,2‘ ‘-aminoethylamine) is reported. Two crystal structures of L1 and three of L2 are reported: the NO3- (1) and SO42- (2) salts of L1, the free base (3) of L2, and the NO3- (4) and TsO- (5) salts of L2.
- A comparative study of the binding of nitrate and sulfate with a polyammonium monocycle L1, (3,6,9,17,20,23-hexaazatricyclo[23.3.1.111,15]-triaconta-1(29),11,13,15(30),25,27-hexaene), and the corollary bicycle L2, (1,4,12,15,18,26,31,39-octaazapentacyclo-[13.13.13.16,10.120,24.133,37]-tetratetraconta-6,7,9,20(43),21,23,33(42),34,36-nonaene), is reported. Potentiometric studies indicated negligible binding for L1 and nitrate, but highaffinity was observed for sulfate (log KH5L(SO4)/H5L·SO4 = 3.53(1), log KH6L(SO4)/H6L·SO4 = 4.36(1)). Stronger bindingwas observed for the cryptand L2 with both nitrate and sulfate (log KH6L(NO3)/H6L·NO3 = 3.11(5), log KH7L(NO3)/H7L·NO3= 3.55(5); log KH6L(SO4)/H6L·SO4 = 4.43(1), log KH7L(SO4)/H7L·SO4 = 4.97(5)). Five crystal structures are reported: thenitrate (1) and sulfate (2) salts of L1, the free base (3) of L2, and the nitrate (4) and tosylate (5) salts of L2.Structural results for L1 indicate relatively planar monocycles with cis and trans orientations of the phenyl groupsfor 2 and 1, respectively, with the anions above and below the monocycle rings. For L2, key features include anencapsulated water and intricate water network in 3, two encapsulated and four external nitrates and two externalwater molecules in 4, and six external tosylates with sulfonate groups pointing into the cavity and eight externalwaters in 5.
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