Phenol, 2-amino-3-fluoro-5-nitro- synthesis

Yield:864074-05-5 72%

Reaction Conditions:

Stage #1: 4-fluoro-6-nitro-1,3-benzoxazol-2-(3H)-onewith sodium hydroxide in water at 100; for 3 h;
Stage #2: with hydrogenchloride in water at 20;

Steps:

25.1

EXAMPLE 25; Preparation of (5S)-N-[3-(5-Fluoro-3-methoxyimino-4-methyl- 3, 4-dihydro-2H-benzo [1, 4] oxazin-7-yl)-2-oxo-oxazolidin-5-ylmethyl]-acetamide; Step 1: Preparation of 2-amino-3-fluoro-5-nitro-phenol; 4-Fluoro-6-nitro-1, 3-benzoxazol-2 (3H) -one (prepared according to the method described in WO/03072553) (5.0 g, 0.02 mol) and sodium hydroxide (5.05 g, 0.126 mol) in water (125 ml) is heated at 100 °C for 3 h. The reaction mixture is cooled to room temperature and carefully neutralized with 6N hydrochloric acid. The resulting precipitate is filtered, washed with water and dried under vacuum to provide pure the title compound as orange solid (3.1 g, 72%); HPLC r. t. 4.05 min.

References:

WO2005/82897,2005,A1 Location in patent:Page/Page column 53