Croatica Chemica Acta, Vol. 69 No. 3, 1996.
Original scientific paper
Merocyanine Isomers of Spiro[indolino-indolopyrans]: 1H and 13C NMRand X-ray Crystal Structure Study
Silvana Raić
; Department of Organic Chemistry, Faculty of Chemical Engineering and Technology , University of Zagreb, Marulićev trg 20, 10000 Zagreb, Croatia
Jasna Vorkapić-Furač
; Faculty of Food Technology and Biotechnology, Pirotijeva 6, University of Zagreb.Croatia
Antonija Hergold-Brundić
; Laboratory of General and Inorganic Chemistry, Faculty of Science, University of Zagreb, Zvonimirova 8, 10000 Zagreb, Croatia
Ante Nagl
; Laboratory of General and Inorganic Chemistry, Faculty of Science, University of Zagreb, Zvonimirova 8, 10000 Zagreb, Croatia
Mladen Mintas
; Department of Organic Chemistry, Faculty of Chemical Engineering and Technology , University of Zagreb, Marulićev trg 20, 10000 Zagreb, Croatia
Albrecht Mannschreck
; lnstitut fur Organische Chemie, Universitat Regensburg, D-93040 Regensburg, Germany
Abstract
The synthesis of stable merocyanine isomers 4 and 5 of the corresponding spiro[indolino-indolopyrans] is described. The structure
of 4 and 5 was deduced on the basis of their lH and 13C NMR spectra.
Geometrical data from X-ray structure analysis show that indolo
and indolino rings in 4 are coplanar with the central diene bridge. The bond length shortening of the central single bond and the heterocyclic moieties indicate an electron delocalization over the whole molecule.
Keywords
Hrčak ID:
177126
URI
Publication date:
1.11.1996.
Visits: 592 *