Two new ligands [(E)-4-chloro-2-((9-ethyl-9H-carbazol-3-yl)methyleneamino)phenol, (E)-2-bromo-4-chloro-6-((9-ethyl-9H-carbazol-3-yl)methyleneamino)phenol] and their Cobalt (II), Manganese (II) and Nickel (II) complexes have been synthesized and characterized through various spectroscopic techniques (NMR, UV, IR, Mass etc.). Synthesized compounds have been examined for their catalytic activities in the oxidation reactions of styrene and cyclohexene. Manganese (II) complexes of both ligands showed the highest catalytic activity in alkene oxidations. Synthesized complex compounds proved that they could be used as catalysts in organic reactions requiring high temperatures. Electronic features of all the new compounds have also been reported for the first time with this paper.