TiO2@UiO-68-CIL: A Metal-Organic-Framework-Based Bifunctional Composite Catalyst for a One-Pot Sequential Asymmetric Morita-Baylis-Hillman Reaction.

A chiral ionic liquid (CIL) moiety of a l-pyrrolidin-2-ylimidazole-decorated homochiral UiO-68-type metal-organic framework, UiO-68-CIL (1), was successfully prepared by the combination of a new premodified chiral CIL ligand (H2L-CIL) and ZrCl4 via a solvothermal method. The TiO2-loaded TiO2@UiO-68-CIL (2) was prepared by impregnating 1 in a toluene solution of Ti(OPri)4 and sequential in situ hydrolysis. The obtained 2 can be a bifunctional asymmetric heterogeneous catalyst to successfully promote the one-pot Morita-Baylis-Hillman reaction starting from aromatic alcohols in a tandem way.