Highly efficient Synthesis of per-substituted amino-cyclodextrins under Microwave Irradiation in a closed Cavity

ABSTRACTSynthetic chemists are paying ever more attention to enabling technologies as a means to opening the paths towards the double goal of achieving high efficiency and meeting green criteria. Non-conventional techniques that create unique environments which promote selective modification have been investigated by many as part of the search for more highly efficient synthetic derivatization of cyclodextrins (CD). A few optimized microwave-assisted protocols have so far been developed for the preparation of selective per-alkylated aminocyclodextrin. In this work, a series of β-CD derivatives, whose primary hydroxyls were all replaced by amino groups, has efficiently been synthesized from per-(6-iodo-6-deoxy)-β-CD via nucleophilic substitution with amines under microwave irradiation in closed vessel (N2 pressure). The reduction of per-(6-azido-6-deoxy)-β-CD to per-(6-amino-6-deoxy)-β-CD via catalytic hydrogenation has also been successfully carried out under dielectric heating.