Reaction #42463

Reaction equation

chloroacetyl chloride

Methyl 3-amino-4-hydroxy-5-iodobenzoate

sodium bicarbonate

→

title compound

Yield 91.8%

Methyl 8-iodo-3-oxo-3,4-dihydro-2H-1,4-benzoxazine-6-carboxylate

Yield 91.8%

Solvents

isobutyl methyl ketone water

Conditions

Workup

1. 1
   Temperatureheated
2. 2
   Temperatureat reflux for 18 h
3. 3
   workup.WAITAfter overnight
4. 4
   Othera beige solid formed
5. 5
   FiltrationThe mixture was filtered
6. 6
   Washwashed with water and hexanes

Procedure

To an ice-cold, stirred solution of Methyl 3-amino-4-hydroxy-5-iodobenzoate (2.3 g) and sodium bicarbonate (1.5 g) in 1:1 isobutyl methyl ketone/water (80 mL) was added chloroacetyl chloride (1.1 g), and the reaction mixture was stirred for 1 h. The mixture was warmed to room temperature and heated at reflux for 18 h. After overnight, a beige solid formed. The mixture was filtered, and washed with water and hexanes to give 2.4 g of the title compound: 1H NMR (300 MHz, DMSO-d6) δ 10.98, 7.89, 7.47, 4.79, 3.82.

Source