An environmentally benign odorless methodology for the preparation of 1,2-trans-thio- and selenoglycosides is reported. In a one-pot condition, the reductive cleavage of disulfides and diselenides using triethylsilane and borontrifluoride diethyletherate combination followed by the reaction of the in situ generated thiolate and selenoetes with glycosyl acetate derivatives in recyclable room-temperature ionic liquid, [BMIM]BFresulted in excellent yields of thio- and selenoglycosides avoiding the use of obnoxious thiols/selenols and metallic catalysts.