Hydrochloric Acid → tert-Butyl (4-chloropyridin-3-yl)carbamate

Participants

Reaction Steps

To a solution of 3-amino-4-chloropyridine (6.56 g, 51 mmol) in THF (46 mL) is added 2 M NaHMDS in THF (50 mL, 100 mmol). After stirring at rt for 15 min BOC2O (10.1 g, 46.4 mmol) in THF (26 mL) is added in one portion and the mixture is stirred for 3 h at rt. 0.1% aqueous HCl (590 mL) is added. The mixture is extracted with EtOAc. The organic layer is dried (Na2SO4), filtered and concentrated. The residue is purified by silica gel chromatography eluting with 0-50% EtOAc in heptane to afford (4-chloro-pyridin-3-yl)-carbamic acid tert-butyl ester (6.78 g, 76%). MS: 229 (M+H); 1H NMR (300 MHz, CDCl3): δ 9.38 (ms 1H), 8.23 (d, 1H), 7.30 (dd, 1H), 6.85 (broad s, 1H), 1.57 (s, 9H).

Provenance & Evidence