Pyridinium chloride → 1-Nitrodibenzothiophen-4-ol

Participants

Reaction Conditions

Reaction Steps

Solid pyridine hydrochloride (1 kg, 8.7 mol) was added to 4-methoxy-1-nitro-dibenzothiophene (iii)(35.44 g, 187 mmol) and the reaction mixed well before heating to 165° C. with continuous stirring. The mixture was maintained like this for 8 hrs, cooled, diluted with water (500 ml) and extracted into dichloromethane (3×200 ml). 3M sodium hydroxide solution was added to the organic extract until a dark solid precipitated from the solution. The filtrate was removed and the liquor acidified to pH1 using concentrated HCl. The resulting bright yellow solid that formed on acidification was then removed by filtration, washed with water and dried to give the title compound that was suitably pure to be used without any further purification. (35.44 g, 77%) m/z (LC-MS, ESP), RT=3.69 min, (M+H)=246.2, (M−H)=244.1.

Provenance & Evidence