Salicylates are the most important benzoic acid derivatives due to their biological and pharmaceutical activities, and industrial widely applications. In this project, Friedel-Crafts reaction of methoxy benzene (anisole) with methyl chloroformate was utilized for the synthesis of salicylic acid. The effect of catalyst type and amount, temperature and reaction time were investigated in order to optimizing the overall reaction yields. For this purpose different type of alumina, aluminium trichloride, iron trichloride, nickel dichloride and silica gel were used as catalyst. Also, recoverability and friendly green chemistry catalysts such as silica supported aluminium chloride and alumina supported zirconia dioxide were used. The structure of all the synthesized compounds were studied by GC/MS, MASS and characterized by 1 H NMR and FT-IR. Reaction of electron rich 1,3,5-trimethoxy benzene (25) with methyl chloroformate reagent was also examined using FeCl 3 as catalyst. The effect of decreasing the number of electron donating group (methoxy group) in these reactions also was investigated. In theoretical section of this project, the effect of intramolecular hydrogen bonding on stability of products derived from reaction of 1,3,5-trimethoxy benzene (25) , was studied. The structures of 2,4-dimethoxy benzene (23) , dimethyl-2-hydroxy-4,6-dimethoxy isophetalate (27) , methyl-2-hydroxy-4,6-dimethoxy-3-(2,4,6-trimethoxy benzoyl) benzoate (28) , methyl-2,4,6-trimethoxy benzoate (29) , dimethyl-4,6-dihydroxy-2-methoxy isophetalate (30) and methyl-6-hydroxy-2,4-dimethoxy-3-(2,4,6-trimethoxy benzoyl) benzoate (63) were optimized theoretically by performing HF, B3LYP and MP2 levels of theory using the standard 6-31G basis set. Conformational analysis of these compounds was performed. So, the most stable and most unstable conformers of these compounds were determined. The structural isomers (28) and (63) with their tautomers due to distinguished the best and most stable structure were investigated and 1 H NMR spectroscopies of them were calculated by using B3LYP(6-31G) level of theory. The calculated results were compared with the experimental findings and they were in good agreement with the experimental results.