The self-assembly behavior of ionic liquids with acyclic polyethers was studied. The cations of 1-alkyl-3-methylimidazolium salts and 1-alkylpyridinium salts could form complexes at a ratio of 1:1 with poly(ethylene glycol)-800 (PEG800) and poly(propylene glycol)-1000 (PPG1000) in which the chain length was suitable to wrap around the cations. On the basis of the investigation by NMR, mass spectrometry, UV-vis spectroscopy, and TG analysis, the formation and characteristics of the novel complexes were discussed.

Deep-sea Diels-Alder: The asymmetric organocatalytic Diels-Alder reaction of cyclohexenones with aromatic nitroolefins can be carried out in seawater and brine. The reaction proceeds by an in situ enamine activation involving a one-step concerted addition pathway (see scheme).

The efficient simultaneous activation of cyclohexenones or simple alkyl acyclic enones and 2‐hydroxynitrostyrenes was realized by using a prolinol thioether catalyst. Thus, a highly chemo‐, diastereo‐ and enantioselective synthesis of functionalized tetrahydroxanthenones and chromanes with up to three contiguous stereocenters was developed.magnified image

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The asymmetric tandem oxa-Michael-aldol reaction of salicylic aldehyde derivatives with alpha,beta-unsaturated aldehydes catalyzed by a chiral amine/chiral acid organocatalytic system was investigated. The organocatalytic system of (S)-diphenylpyrrolinol trimethylsilyl ether with chiral shift reagent (S)-Mosher acid presented a synergistic effect in the improvement of reaction performance and offered an efficient steric effect in the transformation. The tandem oxa-Michael-aldol reaction proceeded with high yields (up to 90%) and with excellent ee values (up to 99%) to give the corresponding chromene derivatives. The structure of the chiral ammonium salt formed in situ and the corresponding mechanism were also studied by (1)H NMR.