5-chloro-2-methyl-1-oxidopyridin-1-ium

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 5-chloro-2-methylpyridine-N-oxide (9.46 g) in concentrated sulphuric acid (30 ml), a nitration mixture consisting of 30% oleum (28 ml) and fuming nitric acid (47 ml), was added dropwise at 5°-8° over 20 minutes. The reaction mixture was allowed to stand for one hour at room temperature and then heated for 2 hours on a steam bath After allowing to cool the solution was poured onto ice and carefully neutralised with ammonium carbonate, added in portions. The solid was extracted into chloroform, dried, stripped and triturated with petrol to give 5-chloro-4-nitro-2-methylpyridine-N-oxide, (9.83 g), m.p.120°-122° was added dropwise at 5°-8° over 20 minutes heated for 2 hours on a steam bath to cool the solution was poured onto ice added in portions The solid was extracted into chloroform dried triturated with petrol