Water → tert-Butyl (4-(2-hydroxyethyl)pyridin-2-yl)carbamate

Participants

Reaction Conditions

Reaction Steps

To a solution of ethyl 2-(2-(tert-butoxycarbonylamino)pyridin-4-yl)acetate (19) (WO 2007089512) (10.0 g, 35.7 mmol) under nitrogen in THF (100 mL), at −78° C., was added DIBAL (1M solution in THF, 71.3 mL, 71.3 mmol) over 1 hr. The reaction mixture was stirred at −78 to −60° C. for 40 min and then warmed to −15° C. over 1 hr. The solution was re-cooled to −78° C. and treated with further DIBAL (1M solution in THF, 35 mL, 35.7 mmol). The mixture was allowed to warm to −40° C. and stirred for 1 hr. Water (10 mL) was added cautiously to quench the reaction followed by MgSO4 (20 g) and the solids removed by filtration. The filtrate was evaporated to dryness in vacuo and the residue subjected to column chromatography (SiO2, 330 g, 65% EtOAc in hexanes) to give the title compound (20) (6.00 g, 64%) as a yellow solid: m/z 239 (M+H)+ (ES+).

Provenance & Evidence