DIMETHYLAMINO-SUBSTITUTED 7H-BENZO[<i>de</i>]PYRAZOLO[5,1-<i>a</i>]ISOQUINOLIN-7-ONES AND THEIR BEHAVIOR UNDER VILSMEIER–HAACK CONDITIONS

Authors

  • О. Н. Любенко Institute of Monocrystals, Ukraine National Academy of Sciences, Kharkov 61001
  • И. Г. Ермоленко Institute of Monocrystals, Ukraine National Academy of Sciences, Kharkov 61001
  • Л. Д. Паценкер Institute of Monocrystals, Ukraine National Academy of Sciences, Kharkov 61001
  • Б. М. Красовицкий Institute of Monocrystals, Ukraine National Academy of Sciences, Kharkov 61001
  • И. Н. Тур Institute of Monocrystals, Ukraine National Academy of Sciences, Kharkov 61001

Keywords:

7H-benzo[de]pyrazolo[5,1-a]isoquinoline-7-ones, quinazolinium salts, heterocyclization, the Vilsmeier–Haack reaction

Abstract

The behavior of dimethylamino-substituted 7H-benzo[de]pyrazolo[5,1-a]isoquinoline-7-ones, synthesized for the first time, under conditions of the Vilsmeier–Haack reaction. It has been shown that, on heating with POCl3 and DMF, they are converted by electrophilic substitution at the position ortho to the dimethylamino group, followed by cyclization of the iminium adduct to a quinazolinium salt. When an acetyl group is present, the Arnold reaction, leading to the formation of a chloroaryl, accompanies the heterocyclization. The rates and proportion of the reaction products depend on the position of the dimethyl groups relative to the pyrazole ring.

How to Cite
Lyubenko, O. N.; Ermolenko, I. G.; Patsenker, L. D.; Krasovitskii, B. M.; Tur, I. N. Chem. Heterocycl. Compd. 2003, 39, 511. [Khim. Geterotsikl. Soedin. 2003, 594.]

For this article in the English edition, see DOI https://doi.org/10.1023/A:1024773632076

Published

2003-04-25

Issue

Section

Original Papers