Solvent-Free Conversion of Alcohols to Alkyl Iodides and One-Pot Elaborations Thereof

Combination of iodine and triphenylphosphine in the presence of a slight stoichiometric excess of 2,6-lutidine provided effective iodination of alcohols under solvent–free conditions. Several substrates with different polarity, not necessarily soluble in the reaction system, were iodinated in short times without the need for microwave irradiation, ultrasonication or ionic liquids. The scope of this method with complex molecules was especially demonstrated in the fast and selective iodination of primary hydroxyl groups on both protected and unprotected carbohydrates, proving compatible with a variety of functional groups. In addition, a large number of one – pot elaborations of alkyl iodides thus obtained was successfully performed through the application of unprecedented fully solvent – free sequences. In particular, direct installation of either nitrogen or sulfur functionalities and generation of useful saccharide building – blocks were achieved in remarkably short times avoiding the use of polar high boiling solvents