Efficient synthesis of α,ω-dibromodideoxyalditols as precursors for α,ω-dithioalkylalditols

The regioselective bromination of unprotected alditols (d-arabinitol, xylitol, ribitol, d-glucitol, and d-mannitol) was achieved with acetyl bromide as the brominating reagent. The α,ω-dibromodideoxyalditols were isolated after acetylation in good overall yields (51–80%). 1,5-Dithioalkylpentitols, 1,6-dithioalkyl-d-mannitol, and d-glucitol were obtained from the dibromo derivatives and sodium alkanethiolates (with R = n-butyl, n-octyl, n-dodecyl, and n-hexadecyl).