Benzyl Bromide → 7-Nitro-4-benzyloxy-1,2-benzisothiazole

Participants

Reaction Steps

200 g of 7-nitro-4-hydroxy-1,2-benzisothiazole, 260 g of benzyl bromide and 210 g of potassium carbonate in 2.5 l of acetone are refluxed for 12 hours. The entire mixture is then concentrated to one liter under reduced pressure, the residue is poured into a threefold amount of water and the batch is repeatedly extracted with methylene chloride. The combined organic phases are dried over magnesium sulfate and freed from solvent under reduced pressure. The crude product is recrystallized from a mixture of methanol and tetrahydrofuran. 200 g (70% of theory) of 7-nitro-4-benzyloxy-1,2-benzisothiazole of melting point 158°-160° C. are obtained.

Provenance & Evidence