Triethylamine → 3-Chloro-7-methylbenzo[d]isoxazole

Participants

Reaction Conditions

Reaction Steps

To a stirred mixture of 114 parts of 1,2-benzisoxazol-3-ol and 230 parts of phosphoryl chloride were added dropwise 160 parts of N,N-diethylethanamine (exothermic reaction). Upon complete addition, the reaction mixture was stirred overnight at 135° C. The mixture was poured into crushed ice and the product was extracted with trichloromethane. The extract was dried, filtered and evaporated. The residue was boiled in 2,2'-oxybispropane. The solvent was decanted (this was repeated twice) and the residue was purified by column chromatography over silica gel using a mixture of trichloromethane and methanol (97:3 by volume) as eluent. The pure fractions were collected and the eluent was evaporated, yielding 60 parts (51.1%) of 3-chloro-7-methyl-1,2-benzisoxazole as a residue (int. 1).

Provenance & Evidence