6-(2-tert-Butoxycarbonylamino-1-hydroxy-ethyl)-nicotinic acid (130 mg, 0.461 mmol), diisopropylethylamine (DIPEA) (0.426 mL, 2.44 mmol), [(benzotriazol-1-yloxy)-dimethylamino-methylene]-dimethyl-ammonium tetrafluoroborate (319 mg, 1.00 mmol), and benzyl amine (0.246 mL, 2.30 mmol) were dissolved into 3 mL of dry DMF and stirred overnight. LC-MS indicated formation of the coupled product. The mixture was diluted with 30 mL of EtOAc, the organic phase washed with 2×20 mL H2O and 1×20 mL of brine, dried (MgSO4) filtered and concentrated. The residue was dissolved in CH2Cll2, applied to a SiO2 column and purified (10–30% EtOAc/hexanes) to give 47.8, 27.9% of [2-(5-benzylcarbamoyl-pyridin-2-yl)-2-hydroxy-ethyl]-carbamic acid tert-butyl ester.
