Cesium carbonate → 4-(3-chloropropyl)-2H-1,4-benzoxazin-3(4H)-one

Participants

Reaction Steps

A reaction flask was charged with 4H-benzo[1.4]oxazin-3-one (1.48 g, 10 mmol), 1-chloro-3-iodopropane (2.04 g, 10 mmol), and Cs2CO3 (4.88 g, 15 mmol) in MeCN (10 mL) and stirred at rt for 40 h. The reaction mixture was quenched with water and the product extracted into EtOAc. The combined organic phases were dried over Na2SO4, filtered, and concentrated. The product was purified by flash column chromatography (SiO2; n-heptane/EtOAc 2:1) to give the title compound (1.97 g, 88%). 1H NMR (CDCl3) d 7.06-7.02 (m, 2H), 7.01-6.99 (m, 2H), 4.58 (s, 2H), 4.12-4.07 (m, 2H), 3.64-3.60 (m, 2H), 2.19-2.12 (m, 2); 13C NMR (CDCl3) d 164.7, 145.6, 128.6, 124.2, 123.2, 117.5, 114.9, 67.8, 42.6, 39.1, 30.3.

Provenance & Evidence