Vitamin B12 is a cofactor for many enzymes, but it also functions as a catalyst in C-C bond-forming reactions. Herein, the impact of corrin structural modifications on their catalytic efficacy was examined. Derivatives with various substituents at c-, d-, and meso-positions were synthesised by using traditional and new microwave methodologies, and then tested in the model reaction of 1,1-diphenylethylene with ethyl diazoacetate. To complement the experimental data, cyclic voltammetry and DFT calculations were performed. Mainly alterations at the c- or d-positions influence both the reaction yield and selectivity.
Keywords: diazo compounds; homogeneous catalysis; natural products; structure-activity relationships; substituent effects.
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