O-(4-chlorophenyl)hydroxylamine

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Hydrazine hydrate (0.56 mL, 12 mmol) was added to a solution of Example 3A (820 mg, 3.0 mmol) in chloroform (37 mL) and methanol (4 mL). The suspension was stirred at room temperature for 22 hours. Silica gel (10 g) was added, and the mixture was concentrated to dryness. The residue was applied to the top of a flash chromatography column and eluted with hexanes-ethyl acetate (80:20) to provide the title compound as the free amine. The residue was dissolved in ethanol (5 mL) and treated with HCl/dioxane (4M, 1 mL). The solution was heated at reflux and diluted with gradual addition of ethyl acetate (50 mL). The mixture was cooled to room temperature and filtered to provide the title compound as a hydrochloride salt. 1H NMR (300 MHz, CD3OD) δ 7.15-7.22 (m, 2 H), 7.42-7.49 (m, 2 H). Silica gel (10 g) was added the mixture was concentrated to dryness eluted with hexanes-ethyl acetate (80:20)