Fig. 2
From: Molecular recognition by multiple metal coordination inside wavy-stacked macrocycles
Binding of dicarboxylic acids by Zn-hexapap and the formation of the wavy-stacked dimer. a–i Interaction of dicarboxylic acids H2 4a–H2 4i and Zn-hexapap [1Zn6(acac)6].(1H NMR, 600 MHz, CDCl3/CD3OD = 10/1 (v/v), 298 K, [1Zn6(acac)6] = 2.5 mM). a Malonic acid H2 4a (m = 1). m indicates the number of methylene groups between the two carboxylic groups. b Succinic acid H2 4b (m = 2). c Glutaric acid H2 4c (m = 3). d Adipic acid H2 4d (m = 4). e Pimelic acid H2 4e (m = 5). See k for assignment of the signals. f Suberic acid H2 4f (m = 6). g Azelaic acid H2 4g (m = 7). h Sebacic acid H2 4h (m = 8). i Dodecanedioic acid H2 4i (m = 10). j 1H–1H ROESY (rotating-frame Overhauser effect spectroscopy) NMR spectrum of the complex with two pimelates 4e 2−, [1 2Zn12 4e 2X n ] (X = labile coordinating ligand) (600 MHz, CDCl3/CD3OD = 10/1 (v/v), 323 K). Yellow circles indicate ROE cross peaks between the top and bottom macrocycles. k Chemical structure of [1 2Zn12 4e 2X n ]. Red arrows indicate the pairs of 1H–1H between which the ROE cross peaks were observed (see Supplementary Fig. 18). See also Fig. 3d for the crystal structure of [1 2Zn12 4e 2(H2O)4Cl8] colored in the same manner. l Emissions from Zn-hexapap during UV irradiation (365 nm) upon binding of a series of dicarboxylic acids H2 4a–H2 4i (10 μM, CHCl3/CH3OH = 10/1 (v/v), 298 K). m A schematic representation of the recognition of dicarboxylic acids in the cavity of the wavy-stacked dimer of the Zn-hexapap
