Synthesis of Pyrrolo[2,3‐g]‐ and Pyrrolo[3,2‐f]quinolines from 5‐Amino‐2,3‐dimethyl‐ and ‐1,2,3‐trimethylindoles with 4,4,4‐Trifluoroacetoacetic Ester.

Abstract

Fused pyridine derivativesFused pyridine derivatives R 0450 Synthesis of Pyrrolo[2,3-g]-and Pyrrolo[3,2-f]quinolines from 5-Amino-2,3-dimethyl-and -1,2,3-trimethylindoles with 4,4,4-Trifluoroacetoacetic Ester. -Condensation reaction of the title 5-aminoindoles (I) with 4,4,4-trifluoroacetoacetate (II) affords regioselectively either enaminocrotonates (III) or amides (V) depending on the reaction conditions. The enaminocrotonates suffer thermal cyclization to furnish pyrrolo[3,2-f]quinolines (IV), and the amides undergo an acid-mediated cyclization to give pyrrolo[2,3-g]quinolines (VI). -(YAMASKHIN, S. A.; ROMANOVA, G. A.; ORESHKINA, E. A.; ZHUKOVA, N. V.; Chem. Heterocycl. Compd. (N. Y.) 42 (2006) 1, 77-85; Ogarev Mordovian State Univ., Saransk 430000, Russia; Eng.) -M. Kowall 40-151