To a solution of 2-(tert-butoxycarbonylamino)-2-p-tolylacetic acid (I40) (1.29 g, 4.86 mmol) in THF (70 ml), are added N,N′-methanediylidenedicyclohexanamine (1.20 g, 5.83 mmol), 1H-benzo[d][1,2,3]triazol-1-ol (0.79 g, 5.83 mmol), and (R)-quinuclidin-3-ol (0.74 g, 5.83 mmol). The reaction was stirred at RT for 15 hours, and then solvent was evaporated. The residue was taken up with DCM, the insoluble solid was filtered off, and the organic solution was washed twice with aq. Na2CO3 and then brine, dried over Na2SO4 and evaporated to dryness. The crude was purified by flash chromatography (EtOAc/MeOH=8/2 to 7/3) to obtain (R)-quinuclidin-3-yl 2-(tert-butoxycarbonylamino)-2-p-tolylacetate (1.03 g; 57% yield).
