A new bis(amine) benzotriazole phenoxide ligand, ^C8NNBTP-H (1) was prepared from the Mannich condensation of 2-(2H-benzotriazol-2-yl)-4-(2,4,4-trimethylpentan-2-yl)phenol with the mixtures of excess paraformaldehyde and N,N,N-trimethylethylenediamine under reflux conditions. Zinc and magnesium complexes bearing the N,N,O-tridentate ^C8NNBTP ligand were synthesized and fully characterized. The reaction of ^C8NNBTP-H with ZnEt₂ (1.2 molar equiv.) in toluene gives the monomeric tetra-coordinated zinc complex [(^C8NNBTP)ZnEt] (2). The homoleptic and monomeric complexes [(^C8NNBTP)₂M] (M = Zn (3) and M = Mg (4)) result from treatment of ZnEt₂ or MgⁿBu₂ with ^C8NNBTP-H (two equiv.), in which the metal center is hexa-coordinated by two tridentate ^C8NNBTP ligands. Luminescent properties and catalysis for lactide (LA) polymerizations of complexes 2–4 are studied. Complexes 2–4 produce bright green fluorescence with emission maxima ranging from 510 to 520 nm in the solid state. Experimental results indicate that complex 2 catalyzes the ring-opening polymerization of LA in the presence of 9-anthracenemethanol (9-AnOH) with efficient catalytic activities in a controlled fashion, yielding poly(rac-lactide) with a slight isotactic predominance (P_m = 0.59).