Selective Monocarbamoylation of Symmetrical Diols with Alkyl Halides and Potassium Cyanate Using Phase-Transfer Catalysis
17 September 2002 (online)
A convenient method for the selective monocarbamoylation of diols by reaction with alkyl isocyanates, generated in situ from alkyl halides and potassium cyanate under phase-transfer catalysis, is described. Under these conditions the ease of reaction shows the following order cis-diols > trans-diols and diols > monoalcohols. An increase in the number of methylene groups between two hydroxyl groups lead to a decrease in product yields. A plausible mechanism to explain these results is proposed.