Potassium Nitrate → HCID 57827875, compound

Participants

Reaction Steps

Specifically, 4-fluoroisoquinoline (3) is nitrified with potassium nitrate in sulfuric acid, to thereby form 4-fluoro-5-nitroisoquinoline (4a) and a position isomer (4b) thereof [step A]. Subsequently, these two products are reduced by use of concentrated hydrochloric acid and stannous chloride dihydrate, to thereby form 4-fluoro-5-aminoisoquinoline (5a) and a position isomer (5b) thereof [step B]. 5-Amino-4-fluoroisoquinoline (5a) is separated through column chromatography for purification [step C]. The purified product is diazotized with sodium nitrite [step D]. The diazo compound is subjected to Sandmeyer reaction employing SO2 gas-saturated acetic acid and cupric chloride dihydrate [step E], to thereby yield 4-fluoroisoquinoline-5-sulfonyl chloride (2a).

Provenance & Evidence