Diisopropylethylamine → HCID 86631949, compound

Participants

Reaction Steps

4-(tert-Butoxycarbonyl)-2-(ethylamino)-3,6-dimethylbenzoic acid (115 mg, 0.392 mmol) was dissolved in tetrahydrofuran (1 mL) and then cooled in an ice bath. N,N-Diisopropylethylamine (0.07 mL, 0.403 mmol) and triphosgene (40 mg, 0.135 mmol) were added, and the mixture was stirred at ambient temperature for 0.5 h. The mixture was quenched with water and extracted with dichloromethane (2×). The combined organic portion was dried over sodium sulfate, then filtered and concentrated to provide tert-butyl 1-ethyl-5,8-dimethyl-2,4-dioxo-2,4-dihydro-1H-benzo[d][1,3]oxazine-7-carboxylate (109 mg, 0.342 mmol, 87% yield). 1H NMR (400 MHz, CDCl3): δ 7.35 (s, 1H), 4.06 (q, 2H), 2.70 (s, 3H), 2.46 (s, 3H), 1.62 (s, 9H), 1.28 (t, 3H); MS (EI) for C17H21NO5: 320 (MH+).

Provenance & Evidence