Fig. 5: Structure−activity relationships.

The differentiation of representative substrates with different sizes and steric hindrance for three-component aza-Darzens reaction catalyzed by Zn₂Er₄L¹₄, Zn₄Er₆L²₆, and Zn₂Er₈L³₈. Reaction condition: anilines (0.5 mmol for A-G), aldehyde (0.6 mmol formaldehyde for A-D; 1.5 mmol propanal for E, 1.0 mmol aromatic aldehyde for F, G), α-diazo ester (0.7 mmol for A-D, F, G; 1.5 mmol for E), catalyst (0.4 mol% for A-E; 0.2 mol% for F, G), time (0.5 h for A-D; 2 h for E; 6 h for F, G), room temperature.