1,4-DIAZABICYCLO[2.2.2]OCTANE (DABCO) - AN EFFICIENT REAGENT IN THE SYNTHESIS OF ALKYL TOSYLATES OR SULFENATES

The bicyclic tertiary amine 1,4-diazabicyclo[2.2.2]octane (DABCO) is a promising substitute not only for the widely used but hazardous and h ygroscopic base pyridine in the syntheses of alkyl tosylates 3 but als o for triethylamine in the preparation of alkyl sulfenates 4 from ster ically hindered alcohols 2. In several provided examples the substrate s 2 were completely converted into the desired products, e.g. the resp ective tosylates 3, which minimized subsequent separation processes. T he current protocol points, in a number of cases, to nonchlorinated so lvents as good alternatives to chloroform or dichloromethane and offer s a workup procedure for a larger scale reaction which relies on the r emoval of the side products by filtration instead of the traditional e xtraction method using several aqueous washings.