Cinnoline誘導体に関する研究(第3報) : 4-(Methylsulfonyl)cinnolineとケトンとの反応について その1

Abstract

Reaction between 4-(methylsulfonyl) cinnoline (I) and ketones, in the presence of sodium amide as a basic catalyst, was examined. The compounds listed used as the ketones were acetophenone (IIa), propiophenone (IIb), butyrophenone (IIc), valerophenone (IId), isovalerophenone (IIe), isobutyrophenone (IIf), acetone (IIg), diethyl ketone (IIh), methyl ethyl ketone (IIi), methyl propyl ketone (IIj), methyl isobutyl ketone (IIk), methyl isopropyl ketone (III), cyclohexanone (IIm), l-p-menthan-3-one (IIn), and cyclopentanone (IIo). The reaction with aromatic ketones (IIa to IIf) afforded the corresponding compounds (IIIa to IIIf), whose hydrolysis in alkaline reaction resulted in their decomposition to the corresponding 4-alkylcinnolines (IVa to IVf) and benzoic acid (Charts 1 and 2; Tables I and II). Symmetric, straight-chain ketones (IIg and IIh) gave the corresponding IIIg and IIIh, while the reaction with asymmetric IIi afforded two kinds of product, IIIi and IIIi'. In the case of other asymmetric ketones, IIj to IIl, only one kind of the corresponding products (IIIi to IIIl) were obtained (Chart 3 and Table I). Among the products obtained by this reaction (IIIa, IIIg, IIIi-l), the products obtained by the reaction of the methyl-carbon adjacent to the carbonyl group may show tautomerism in alcoholic solvent, as indicated by (1) in Chart 4 but they should be present in the keto form in solids or in chloroform solution. Finally, the reaction with cyclic ketone (Im) gave a product (IIIm') which was assumed to have been formed by the decomposition of the primary product, IIIm. The reaction with IIn should afford IIIn, and the product IIIo' from IIIo is assumed to have been formed via IIIo (Chart 6 and Table I).