Simultaneous Clicknetic Resolution Coetaneous catalytic kinetic resolution of alkynes and azides through asymmetric triazole formation

A non-enzymatic simultaneous kinetic resolution of racemic alkynes and racemic azides utilising an asymmetric CuAAC reaction is reported. The use of a CuCl (R,R)Ph-Pybox catalyst system effects a simultaneous kinetic resolution of two racemic starting materials to give one major triazolic diasteroisomer in the ratio 74:12:4:10 (dr 84:16, 90% ee maj). The corresponding control reaction using an achiral copper catalyst gives the four possible diastereoisomers in a 23:27:23:27 ratio, demonstrating minimal inherent substrate control.