Iron(III) chloride as an efficient catalyst for stereoselective synthesis of glycosyl azides and a cocatalyst with Cu(0) for the subsequent click chemistry.

A highly efficient and mild method for azido glycosylation of glycosyl ß-peracetates to 1,2-trans glycosyl azides was developed by using inexpensive FeCl(3) as the catalyst. In addition, we demonstrated, for the first time, that FeCl(3) in combination with copper powder can promote 1,3-dipolar cycloaddition (click chemistry) of azido glycosides with terminal alkynes. Good to excellent yields were obtained with exclusive formation of a single isomer in both glycosyl azidation and subsequent cycloaddition processes.

An efficient reusable silver-exchanged tungstophosphoric acid heterogeneous catalyst for solvent-free intermolecular hydroamination of alkynes.

Hydroamination of alkynes with both aromatic and aliphatic amines proceeds efficiently in the presence of silver-exchanged tungstophosphoric acid (AgTPA) catalyst under solvent-free conditions to afford ketimines in excellent yields.