Readily Accessible Azido-Alkyne-functionalized Monomers for the Synthesis of Cyclodextrin Analogues Using Click Chemistry

A set of linear and cyclic oligomers were synthesized starting from a suitable azido-alkyne monomer through click oligomerization. The synthesis of these monomers starting from bromobenzene features an enzymatic dihydroxylation and the regio- and stereoselective installation of the azide and alkyne functionalities. Optimization of the click reaction was accomplished using dimerization as the model reaction. The product distribution of the oligomerization could be modulated by the monomer concentration and the use of additives, generating mainly cyclic oligomers consisting of tetramers, pentamers and hexamers.