Methyl iodide → 2H-3,1-Benzoxazine-2,4(1H)-dione, 6-chloro-1-methyl-

Participants

Reaction Steps

As illustrated in the scheme above, NaH (2.43 g of a 60% dispersion, 60.8 mmol) was added to a solution of 6-chloro-2H-3,1-benzoxazine-2,4(1H)-dione (10.0 g, 50.6 mmol) dissolved in DMF (200 mL). The resulting mixture was stirred at room temperature for 30 min., and then methyl iodide (6.3 mL, 101 mmol) was added dropwise. After the reaction had stirred at room temperature overnight, it was concentrated in vacuo. Water and brine were added to the residue, and the aqueous layer was extracted with CH2Cl2 (2×). The combined organic phases were dried over Na2SO4, filtered, and concentrated in vacuo. The crude product was triturated with 3:1 hexanes:EtOAc. The solvent was removed by filtration, and the resulting solid was washed with additional 3:1 hexanes:EtOAc, followed by 100% hexanes. The product was dried briefly under vacuum to produce the title compound as a pale yellow solid. (8.59 g, 80%). 1H-NMR (DMSO-d6): δ 7.96 (d, J=2.6 Hz, 1H), 7.89 (dd, J=2.6 Hz, J=9.0 Hz, 1H), 7.48 (d, J=9.0 Hz, 1H), 3.45 (s, 3H). MS (ESI) (M+H)+=212.

Provenance & Evidence