A CCC-NHC pincer Mn complex was prepared and was characterized by 1H and 13C NMR spectroscopy, mass spectroscopy, elemental analysis, and single crystal X-ray crystallography. Its catalytic activities were demonstrated through diverse chemical transformations including cross-coupling borrowing hydrogen reactions and dehydrogenative cyclization reactions, which resulted in the formation of both C–C and C–N bonds. These cascade reactions involved multiple processes, including dehydrogenation, condensation, and hydrogenation. Under optimized conditions, Mn catalyst affectively converted a broad substrate scope. The different reactions yielded saturated ketones (isolated yields, 42 %–92 %), 2-oxindole derivatives (isolated yields, 70 %–83 %), and quinoline derivatives (isolated yields, 70 %–89 %). These atom economical transformations produce only water molecules as by-products enhancing their environmental friendliness. The catalyst utilized earth-abundant Mn potentially reduce costs. Catalytic cycles were proposed for borrowing hydrogen and acceptorless dehydrogenative cyclization reactions based on control experiments. These included oxidation, aldol condensation, and hydrogenation reactions.