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Z. Naturforsch. 2013,
68b, 1031 – 1040
doi:10.5560/ZNB.2013-3102
Synthesis of 4-Aminocoumarin Derivatives with N-Substitutents Containing Hydroxy or Amino Groups
1 Faculty of Pharmacy, Medical University of Sofia, Dunav 2, BG-1000 Sofia, Bulgaria
2 Institute of Organic Chemistry with Centre of Phytochemistry, Acad. G. Bonchev St. 9, BG-1113 Sofia, Bulgaria
3 University of Applied Sciences, Beethovenstr. 1, D-73631 Aalen, Germany
4 Ionic Liquids Technologies GmbH, Salzstrasse 184, D-74076 Heilbronn, Germany
Reprint requests to Prof. Dr. Ivo C. Ivanov. Fax: +359 2 9879874. E-mail:
ivanov43@gmail.com
Received March 21, 2013 / published online September 4, 2013
Dedicated to Professor Willi Kantlehner on the occasion of his 70th birthday
Reactions of 4-hydroxycoumarin (1a) and 4-chlorocoumarin-3-carbaldehyde (1b) with amino alcohols or alkylene diamines led to the formation of the corresponding N-substituted 4-aminocoumarins 3, 5 and 6. However, 4-hydroxycoumarin-3-carbaldehyde (8) reacted with 2-aminoethanol and ethylenediamine to give N-substituted 3-(aminomethylene)-chromane-2,4-diones 9a, b. The structure and the E-configuration of compound 6 were proven by X-ray crystal structure analysis. Products 9a, b displayed signals of both E- and Z-isomers in their NMR spectra. All novel products have been characterized by means of spectral (IR, NMR, MS) data and elemental analyses.
Key words: Hydroxycoumarins, Aminocoumarins, Aminoalcohols, Alkanediamines, Crystal Structure