Synthesis, crystal structure, catecholase and phenoxazinone synthase activities of a mononuclear cobalt(III) complex containing in situ formed tridentate N-donor Schiff base

Abstract

Synthesis and structural characterization of a mononuclear cobalt(III) Schiff base complex is reported. It crystallizes with monoclinic crystal system with P21/n space group with a = 9.9793(4) Å, b = 28.2907(12) Å and c = 13.1233(6) Å, and β = 97.532(3)°. The compound is active to catecholase and phenoxazinone synthase activities in MeOH, and MeOH and MeCN solvents, respectively at room temperature. Each of the reactions was found to be of first order with reaction rate 8.08 × 10−3 min−1 (MeOH) for the catecholase activity and 1.05 × 10−3 min−1 (MeOH) and 3.82 × 10−3 min−1 (MeCN) for the phenoxazinone synthase activity. The turn over numbers for the catecholase activity is 5.02 × 103 h−1 (MeOH) and for the phenoxazinone synthase activity is 4.59 × 103 h−1 (MeOH) and 5.12 × 103 h−1 (MeCN). Substrate-catalyst adduct was tried to be trapped in each case using mass spectrometry.