The Bull-James assembly as a chiral auxiliary and shift reagent in kinetic resolution of alkyne amines by the CuAAC reactionDedicated to the 60th Birthday of Tony Czarnik.1Electronic supplementary information (ESI) available. CCDC 1477891. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c6ob01623e

The Bull-James boronic acid assembly is used simultaneously as a chiral auxiliary for kinetic resolution and as a chiral shift reagent for in situ enantiomeric excess (ee) determination by 1 H NMR spectroscopy. Chiral terminal alkyne-containing amines, and their corresponding chiral triazoles formed via CuAAC, were probed in situ . Selectivity factors of up to s = 4 were imparted and measured, accurate to within ±3% when compared to chiral GC. The Bull-James boronic acid assembly is used simultaneously as a chiral auxiliary for kinetic resolution and as a chiral shift reagent for in situ enantiomeric excess (ee) determination by 1 H NMR spectroscopy.