Phosphorus sulfide (P2S5) → ethyl 2-[4-(4-bromo-2-fluorophenylmethyl)-3,4-dihydro-3-thioxo-2H-1,4-benzothiazin-2-yl]acetate

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Reaction Steps

To 4 ml of toluene was added 440 mg of the compound of Example 20 and 310 mg of phosphorus pentasulfide. After the mixture was heated to reflux for 6 hours, the solvent was distilled off. Methylene chloride was added to the mixture, and the insoluble substance was filtered off and the solvent was distilled off. Then the residue was purified by silica gel chromatography to give 350 mg of ethyl 2-[4-(4-bromo-2-fluorophenylmethyl)-3,4-dihydro-3-thioxo-2H-1,4-benzothiazin-2-yl]acetate. The structural formula and physical data of this compound are shown in Table 24.

Provenance & Evidence