1,4-Dioxane → HCID 57532238, compound

Participants

Reaction Conditions

Reaction Steps

Diphenylphosphorylazide (4.31 mL, 20 mmol) was added to a stirred solution of 4-bromo-3-methyl-5-nitro-benzoic acid (Example 294: step b (5.2 g, 20 mmol)) and diisopropylethylamine (3.66 mL, 21 mmol) in 1,4-dioxane (80 mL) at rt. After 30 minutes at rt, the reaction was heated to 90° C. for 5 min. Trimethylsilylethanol (5.73 mL, 40 mmol) was added and the solution was stirred for 16 h at 95° C. The solvents were removed in vacuo and the residue was partitioned between EtOAc (100 mL) and water (30 mL). The organic layer was further extracted with aq citric acid (3×30 mL), NaHCO3, (2×30 mL) and brine (50 mL). Purification by column chromatography (9:1 Hex/EtOAc) yielded the title compound as a yellow solid. 1H NMR (CDCl3) δ 7.73 (d, 1H, J=2.4 Hz), 7.41 (br d, 1H, J=1.7 Hz), 7.01 (s, 1H), 4.24 (m, 2H), 2.43 (s, 3H), 1.02 (m, 2H), 0.04 (s, 9H).

Provenance & Evidence