Phosphorus oxychloride → 3-Chloro-5-nitrobenzo[d]isoxazole

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-nitro-1,2-benzisoxazol-3-ol (4.00 g, 0.0220 mol) and phosphorus oxychloride (40.0 mL, 65.8 g, 0.429 mol) is placed in a glass bomb, heated at 150-155° C. for two hours, cooled overnight, concentrated in vacuo, diluted with methylene chloride, and brought to about pH 8 with sodium hydrogen carbonate solution. The phases are separated. The organic phase is washed sequentially with water and brine, dried over anhydrous magnesium sulfate, and concentrated in vacuo to obtain a residue. Column chromatography of the residue using silica gel and a methylene chloride/hexanes solution (1:1) gives the title product as an amber oil which is identified by NMR spectral analysis.

Provenance & Evidence