The reductive coupling reaction of butenedioic esters are successfully promoted by SmI2-HMPA-THF-t-BuOH system to offer 1, 2, 3, 4-tetra alkoxy carbonyl butanes at toom temperature in good yields. The same system can also promote the reductive coupling reaction of ethyl α-cyanocinnamate, diethyl benzalmalonate, ethyl α-acetocinnamate and isopropylidene benzalmalonate to give corresponding dimer products respectively.

Key words: ALKENE, BUTANE P, COUPLED, REDUCTION