A series of novel supramolecular organocatalysts of hydroxyprolinamide based on the upper rim of calix[4]arene scaffold have been developed to catalyze enantioselective multi-component Biginelli reaction. Under the optimal conditions, the reactions occurred with moderate-to-excellent enantioselectivities (up to 98% ee). A plausible transition state constructed by the supramolecular interaction of hydrogen bond and cation- between catalysts and substrates has been proposed. supramolecular organocatalyst, calix[4]

Diverse transformations of 2-alkylthiobenzamides have been established to synthesize 2,3-dihydrobenzothiazin-4-ones, benzoisothiazol-3-ones and 2-alkylthiobenzonitriles in the presence of Selectfluor. Both NaI-HI and TFA-Ac2O systems control the selective C−S bond cleavage and...

Unprecedented synthesis of chiral (aza)crown ethers of calix[4]arene derivatives bearing a carboxyl amide bridge was described. The synthesis proceeds through condensation of the corresponding dinitriles with optically active 1,2-aminoalcohols, and is catalyzed by the ZnCl 2 Lewis acid at elevated temperature in a very efficient one-pot process. The cavity of calix[4](aza)crowns can encapsulate methanol molecules by O-H· · ·π interaction, which has been confirmed by X-ray crystal structures and ESI-MS.chiral calix[4](aza)crown, dinitrile, 1,2-aminoalcohol, X-ray crystal structure, inclusion complex

Five chiral calix[4]proline derivatives were designed and synthesized from aminocalix[4]arenes, and their structures were characterized by 1 H NMR, 13 C NMR, IR, ESI-MS and elemental analysis. The chiral recognition ability for enantiomers of mandelic acid was investigated by NMR techniques, and the results showed that 5,11-diprolinamides substituted calix[4]arene 2b could well and selectively recognize the two enantiomers of mandelic acid (K L /K D 94). A possible recognition mechanism was proposed, which was constructed by cooperative multi-supramolecular interactions including intermolecular acid-base, hydrogen bond and π•••π stacking interactions.