Quinolines and uracils from reactions of isocyanates with aliphatic aldehydes

Abstract

Reactions of phenyl isocyanate (1a) with n-alkanaldehydes (2a—c) afforded 3-alkyl-4-anilinoquinolines (3a—c), 5-alkyl-1,3-diphenyluracils (4a—c), and diphenylurea (5a). Upon treatment of (1a) with isobutyraldehyde (2d), the dihydrouracil derivative (13) was obtained. From the reactions of α-naphtyl isocyanate (1d) with n-alkanaldehydes (2a and b), 3-alkyl-4-α-naphthylaminobenzo[h]quinolines (21a and b) and 2,3-dialkylbenzo[h]quinolines (22a and b) were isolated. On the other hand, 2,3-dialkylbenzo[f]quinolines (28a and b), β-naphthylamine, and urea (5e) were isolated from the corresponding reactions of β-naphthyl isocyanate (1e). The routes to these products are discussed.