The development of an active and efficient electrocatalyst for the oxygen evolution reaction remains indispensable for the smooth running of an electrolyzer. Herein, we have synthesized two cobalt metal-organic frameworks (Co-MOFs) with the formulas [C6H6CoN2O4] (compound 1) and [C12H10CoN2O4] (compound 2) using pyrazine and 4,4'-bipyridine as linkers in dimethylformamide medium by a solvothermal method. Both Co-MOFs shows strong antiferromagnetic interactions with Theta(p) = -70 and -61 K for compounds 1 and 2, respectively. The in situ transformation of both compounds catalyzes the OER efficiently in alkaline medium, affording a current density of 10 mA/cm(2) at overpotentials of 276 +/- 3 and 302 +/- 3 mV by compounds 1 and 2, respectively. Moreover, compound 1 shows a very high turnover frequency (15.087 s(-1)), lower Tafel slope (56 mV/dec), and greater Faradaic efficiency of 95.42% in comparison to compound 2. The transformations of the Co-MOFs have been accessed by employing powder X-ray diffraction (PXRD), high-resolution transmission electron microscopic (HRTEM) analysis, and X-ray photoelectron spectroscopy, which reveal the formation of uniform hexagonal Co(OH)(2) plates. Therefore, the as-developed Co-MOF is found to be an efficient pre-electrocatalyst for the OER in alkaline medium. These results not only reveal the preparation of OER electrocatalysts from a Co-MOF but also establish a method to derive a potentially active electrocatalyst to substitute for the traditional noble-metal-based materials.