Solvent-Induced Amphiphilic Molecular Baskets:  Unimolecular Reversed Micelles with Different Size, Shape, and Flexibility

Abstract

Amphiphilic molecular baskets were obtained by attaching facially amphiphilic cholate groups to a covalent scaffold (calix[4]arene or 1,3,5-2,4,6-hexasubstituted benzene). In a solvent mixture consisting of mostly a nonpolar solvent (i.e., CCl4) and a polar solvent (i.e., DMSO), the hydrophilic faces of cholates turned inward to form a reversed-micelle-like conformer whose stability was strongly influenced by the number of the cholates and the topology of the scaffold. Preferential solvation of the hydrophilic faces of cholates within the molecule by the polar solvent was cooperative and gave the fundamental driving force to the conformational change. The reversed-micelle-like conformer was most stable in structures that allowed multiple cholates to form a microenvironment that could efficiently enrich the polar solvent molecules from the bulk solvent mixture. Disciplines Chemistry CommentsReprinted (adapted) Amphiphilic molecular baskets were obtained by attaching facially amphiphilic cholate groups to a covalent scaffold (calix[4]arene or 1,3,5-2,4,6-hexasubstituted benzene). In a solvent mixture consisting of mostly a nonpolar solvent (i.e., CCl 4 ) and a polar solvent (i.e., DMSO), the hydrophilic faces of cholates turned inward to form a reversed-micelle-like conformer whose stability was strongly influenced by the number of the cholates and the topology of the scaffold. Preferential solvation of the hydrophilic faces of cholates within the molecule by the polar solvent was cooperative and gave the fundamental driving force to the conformational change. The reversed-micelle-like conformer was most stable in structures that allowed multiple cholates to form a microenvironment that could efficiently enrich the polar solvent molecules from the bulk solvent mixture.

Poly(p‐phenylene ethynylene)s with Facially Amphiphilic Pendant Groups: Solvatochromism and Supramolecular Assemblies

“…[14] As described in the Introduction, cholic acid is an interesting compound that is uniquely suitable for solvophobically driven conformational changes. [15] The integration of such an environmentally sensitive building block into the conjugated p system was expected to endow the prepared polymers with remarkable solvatochromism. Figure 2a shows the UV/Vis absorption spectra of P1 in dioxane/water mixtures.…”

Synthesis of Cholate-Based Nicotinamide Adenine Diuncleotide Hydrogen Models and Their Enzyme Mimic Asymmetric Reduction Ability

“…然后采用叠氮化钠为亲核试剂, 将 甲烷磺酸酯基转化成叠氮基, 得到叠氮基胆酸甲酯 [15] . 12.52, 17.30, 23.19, 23.24, 24.56, 26.05, 26.36, 27.49, 28.53, 30.88, 31.11, 31.43, 33.42, 34.33, 35.25, 35.30, 37.68, 39.46, 41.77, 有机化学 研究简报 46.32, 46.52, 47.16, 51.50, 68.25, 72.94, 123.58, 1130.92, 35.28, 147.70, 151.91, 165.14, 174.82;IR (KBr) ν: 3435, 2973, 2868, 1724, 1645, 1527, 1439, 1375, 1251, 1195 11.61, 16.23, 22.06, 22.86, 24.00, 26.17, 27.27, 28.38, 30.49, 30.85, 32.96, 34.10, 34.90, 35.36, 37.08, 39.56, 41.61, 46.16, 46.61, 46.78, 50.61, 67.73, 72.62, 119.85, 131.91, 135.42, 137.61, 144.96, 167.38, 175.14;IR (KBr) ν: 3373, 2939, 2868, 1724, 1639, 1528, 1439, 1271, 1090, 1039 12.54, 17.34, 23.12, 23.19, 24.53, 26.12, 26.37, 26.45, 28.56, 30.88, 31.10, 31.34, 33.52, 34.30, 35.25, 37.51, 39.43, 41.83, 46.32, 46.55, 47.22, 51.51, 68.25, 72.98, 130.53, 150.24, 156.26, 164.66, 174.79;IR (KBr) ν: 3443, 2939, 2868, 1724, 1649, 1528, 1437, 1377, 1270 14.27, 18.88, 24.61, 25.50, 26.55, 28.81, 29.94, 31.01, 33.14, 33.38, 33.51, 35.45, 36.69, 37.57, 38.03, 39.61, 42.21, 44.28, 48.82, 49.26, 50.32, 67.20, 70.34, 75.24, 130.62, 131.66, 132.01, 132.42, 135.52, 138.34, 147.10, 148.36, 164.85, 177.77;IR (KBr) ν: 3420, 3063, 2937, 2868, 1734, 1663, 1539, 1497, 1456…”

Synthesis, Crystal Structure, and DNA‐Cleaving Behavior of 5‐Substituted Benzene‐1,3‐bis(methylene)‐Spaced Dinuclear Copper(II) Complexes

“…Ligands L1 and L2. Methyl 3,5-dimethylbenzoate [15] and 3,5-dimethylbenzamide [16] were synthesized with 3,5-dimethylbenzoic acid as the starting material. Then, methyl 3,5-bis(bromomethyl)benzoate and 3,5-bis(bromomethyl)benzamide were obtained by bromidation with NBS according to the procedure described in [17].…”