Hydroxylamine Hydrochloride

• 1,3-Diphenyl-1,3-propanedione [D0910]
• Hydroxylamine Hydrochloride [H1581]
• Ethanol

Hydroxyamine hydrochloride (396 mg, 6.0 mmol, 1.2 eq.) was added to a solution of 1,3-diphenyl-1,3-propanedione (1.12 g, 5.0 mmol) in EtOH (20 mL) at room temperature and the mixture was refluxed for overnight. Then water (80 mL) was added to the reaction mixture and precipitate was filtered to give 3,5-diphenylisoxazole as a pale red solid (1.09 g, 99% yield).

The reaction mixture was monitored by UPLC.

3,5-Diphenylisoxazole

¹H NMR (400 MHz, CDCl₃); δ 7.87-7.83 (m, 4H), 7.50-7.46 (m, 6H), 6.82 (s, 1H).

• Photocycloaddition of aromatic and aliphatic aldehydes to isoxazoles: Cycloaddition reactivity and stability studies
• A. G. Griesbeck, M. Franke, J. Neudörfl, H. Kotaka, Beilstein J. Org. Chem. 2011, 7, 127.