As evidenced by previous research, photochemical reaction of terminal acetylene and ironpentacarbonyl produces a variety of products with slight changes in reaction conditions. The time of UV-irradiation is one of the most important parameter which decide the selectivity of the product of the reaction. In this report, a novel method for the synthesis of a (tricarbonyl)iron complex of δ-lactone/2-pyranone has been achieved by photochemical reaction of trimethylsilyl acetylene, ironpentacarbonyl and iso-propanol. The pyranone ring was formed by the cyclization of acetylene, iso-propanol and carbonmonoxide. Further, the Fe(CO)3 moiety coordinatively attaches to the π-electron clouds of lactone ring. The successful transformation of 2-pyranone from the (tricarbonyl)iron complex of 2-pyranone was also established by following the demetalation of Fe(CO)3. The formation of (tricarbonyl)iron complex and 2-pyranone were confirmed by various spectroscopic techniques, which includes the 1H, 13C and mass spectrometry. Moreover, the molecular structure of (tricarbonyl)iron complex of δ-lactone or 2-pyranone was established by the single crystal X-ray diffraction analysis.