Borontrifluoride etherate/iodide ion rapidly deoxygenates α-ketooxiranes, 3 , to the corresponding α,β -unsaturatad carbonyl compounds, 4 , in near quantitative yields. In contrast, the reaction of 3 with borontrifluoride etherate/bromide ion, 2 , yielded the corresponding 2-bromo-2-enone derivatives, 5 , in excellent yields. The reagent 1 , also dehalogsnates a variety of 2-bromo-2-enones, 5 , to tha corresponding 2-en-1-one derivatives, 4 , in high yields. We have recently reported that a combination of borontrifluoride etharate/halide ions (X=I, 1 ; X=Br, 2 ) performas number of useful synthetic transformations, e.g., cleavage of alkyl ethers to the halides and alcohols 2 , non-aqueous conversion of acatals and ketals to the carbonyl compounds 3 , and conversion of activated alcohols to the halides 4. Vankar et al have also reported independantly the deoxyganation of sulfoxides to sulfide 5 and the selective cleavage of benzyl ethers 6 with the reagent, 1 . In continuation of our work, we report herein an efficient deoxygenation of α-ketooxiranes, 3 (eqn.1) and dehalogenation of 2-bromo-2-enone, 5 (eqn.2) to the corresponding α, β-unsaturated carbonyl compounds, 4 , with the reagent, 1 .