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Abstract: Two pyrrole-2-carboxylates, tris[2-(2-pyrryl-carboxy)ethyl]amine (1) and tetrakis(2-pyrryl-carboxy-methyl)methane (2), were prepared by the treatment of 2-trichloroacetylpyrrole with tri(2-hydroxylethyl)amine and pentaerythritol, respectively. Hexagonal and grid supramolecular structures were obtained from the self-assembly of 1 and 2, respectively. From the assembly structure, a novel supramolecular synthon of the pyrrole-2-carbonyl dimer has been found. The synthon was demonstrated to be robust by our density functional calculation. It is expected to be useful in the self-assembly of crystal engineering. [Copyright &y& Elsevier]

Abstract: A new series of acyclic anion receptors (1–4) based on methyl 5-(aminomethyl)-1H-pyrrole-2-carboxylate were designed and synthesized. The anion recognition properties of these receptors were examined by 1H NMR spectroscopy and rationalized by density functional theoretical calculation. Receptor 1 displays the highest affinity and selectivity for anionic guests mainly due to the intramolecular hydrogen bonds and rigid molecular geometry. [Copyright &y& Elsevier]

In this paper, we described the conversion of tube to chain assembly of threonine-based cyclophanes by variation of the steric demand of molecules. The interesting properties of these cyclophanes in hosting hydroxyl-containing guest molecules through three-centered hydrogen bonding and the C–H⋯O hydrogen bonds were also reported. [Copyright &y& Elsevier]

The proline catalyzed aldol reactions of nitrobenzaldehydes with various ketones in aqueous anionic micelles were investigated. Both the selectivities and reaction yields were observed to be higher than those of the corresponding reactions in organic solvents. A reaction mechanism is proposed that is somewhat different from that in organic solvents. [Copyright &y& Elsevier]