Mixed-Metal Cu-Mn iminodiacetate coordination polymer as heterogeneous catalyst for Morita-Baylis-Hillman reactions

•Bimetallic Cu:Mn iminodiacetate was prepared with molar ratio 0.8:0.2.•Catalytic activity for Morita-Baylis-Hillman was investigated in mild conditions.•High yields and low reaction times were obtained, similar or superior to literature.•The catalyst shows high performance at least for four catalytic cycles. Coordination polymers (CPs) have been on focus as a breakthrough material to catalyze organic reactions, especially CC bond formations. Recently, few reports showed potentialities of CPs as new catalysts for Morita-Baylis-Hillman (MBH) reactions, but still with unsatisfactory yields and reaction times. Thus, this work explores the synthesis and characterization of a mixed-metal copper-manganese iminodiacetate 1D coordination polymer, named here Cu/Mn-IDA and its application as catalyst for MBH reaction. The catalyst was obtained at room temperature synthesis, characterized by infrared absorption spectroscopy (FT-IR), X-ray powder diffraction (XRD) and CHN elemental analysis. The Cu/Mn molar ration was found by Rietveld refinement, confirming a proportion 0.8:0.2 between copper and manganese ions. In the catalytic assays, the catalyst loading, nature and loading of tertiary amine promoter were investigated using 3-nitrobenzaldehyde as model substrate. The results indicate DABCO (100 mol%) as the best promoter for the reaction in the presence of 22 mol% of catalyst. Optimized conditions were applied for several aldehydes as substrates with yields up to 87%. Results suggests higher influence of nature and position of the substituent groups on the yield and reaction time. The catalyst recyclability was also investigated and showing that the material keeps the same performance for at least 4 catalytic cycles. [Display omitted]