Dimethyl maleate (DMM) is a reactive dienophile and undergoes ultrasonic irradiation promoted Diels-Alder reaction with substituted furans. Mesoporous siliceous SBA-15-supported Cu catalyzed gas phase hydrogenolysis of DMM to 1,4-butanediol (BDO) has been reported. Aluminium chloride has been reported to accelerate the Diels-Alder reaction of DMM and anthracene. DMM can be synthesized by the esterification of maleic anhydride with sulfuric acid and methanol.