The synthesis of tricarbonyl(N-methylisatin)chromium(0) (6) was achieved by protection of the keto functionality of the ligand as an acetal followed by complexation with tricarbonyl(naphthalene)chromium(0) and subsequent deprotection with formic acid. In order to obtain a removable substituent at nitrogen, N-methoxyethoxymethyl (N-MEM) substituted isatin 12 was prepared. Upon acetalization with trimethylformiate