Knorr Quinoline Synthesis

L. Knorr, Ann. 236, 69 (1886); 245, 357, 378 (1888).

Formation of α-hydroxyquinolines from β-ketoesters and arylamines above 100°. The intermediate anilide undergoes cyclization by dehydration with concentrated sulfuric acid:

F. W. Bergstrom, Chem. Rev. 35, 157 (1944); C. R. Hauser, G. A. Reynolds, J. Am. Chem. Soc. 70, 2402 (1948); Org. Syn. coll. vol. III, 593 (1955); R. C. Elderfield, Heterocyclic Compounds 4, 30 (1952); A. J. Hodgkinson, B. Staskum, J. Org. Chem. 34, 1709 (1969). Synthetic application: P. López-Alvarado et al., Synthesis 1998, 186. Cf. Doebner-Miller Reaction; Gould-Jacobs Reaction.