On 2-nitroquinoline

Abstract

2-Nitroquinoline (I) is formed, together with carbostyril (III) when 2-iodoquinoline (II) is reacted with sodium nitrite in dimethylformamide or in dimethyl sulfoxide (Chart 1). Cataltic reduction of I over Raney nickel catalyst, at ordinary temperature and pressure, gives 2-aminoquinoline (IV) while reduction with glucose or arsenious acid, in the presence of sodium hydroxide, affords 2, 2'-azodiquinoline (V) as the product (Chart 2). The nitro group in I easily undergoes substitution with various nucleophilic reagents (Chart 3) but does not react with phenylmagnesium bromide or phenyllithium at ordinary temperature. I also does not react with ethyl cyanoacetate when heated in benzene, in the presence of sodium amide, but when heated in dimethyl sulfoxide, in the presence of potassium cyanide, they react to form ethyl α-cyano-2-quinolineacetate (XI), though in a low yield. XI is also formed from II by a similar sequence of reaction (Chart 4).