tert-Butanol → tert-Butyl naphthalen-2-ylcarbamate

Participants

Reaction Steps

2-Naphthoic acid (S13-1; 2.5 g, 14.3 mmol) in tert-BuOH (85 mL) and toluene (85 mL) was treated with Et3N (2.3 mL, 16.4 mmol), 3 Å molecular sieves (16.7 g) and diphenyl phosphorylazide (3.5 mL, 16.4 mmol). The reaction mixture was refluxed for 24 h. After cooling to rt, solid was filtered off through Celite and the solvent was removed under reduced pressure. The residue was dissolved in EtOAc (75 mL) and washed with 1N aqueous HCl (2×50 mL), saturated aqueous NaHCO3 (2×50 mL), dried over sodium sulfate and concentrated under reduced pressure. Chromatography (10% EtOAc in hexanes) afforded 2.5 g (71%) of S13-2. 1H NMR (500 MHz, CDCl3) δ 7.99 (s, 1H), 7.72-7.78 (m, 3H), 7.44 (t, J=7.8 Hz, 1H), 7.31-7.38 (m, 2H), 6.61 (br s, 1H), 1.55 (s, 9H); MS (ESI) m/z 244.02 [M+H]+.

Provenance & Evidence