- Crystallographic studies on a series of salts of 2,3,7-trihydroxy-9-phenyl-fluorone
-
2,3,7-Trihydroxy-9-phenyl-fluorone (hereafter H3Z) has been synthesised in its H4Z+, H3Z, H2Z- and Z3- protonation states. X-ray crystal structure determinations have been carried out for (H4Z)(HSO4), H3Z, [EtiPr2NH]H2Z, solvated (PPh4)H2Z and solvated K3Z. In each of these salts the 9-phenyl group adopts a different orientation so as to be involved in intermolecular aromatic interactions. The 3- and 6-phenolic carbon-oxygen bond lengths show that double bond character can be delocalised from the ketone to the deprotonated phenoxide across the conjugated π system of the fluorone.
- Abrahams, Brendan F.,McCormick, Laura J.,Robson, Richard
-
experimental part
p. 466 - 471
(2009/07/18)
-
- Reliable synthesis of 9-aryl-substituted 2,6,7-trihydroxyxanthen-3-ones
-
2,6,7-Trihydroxyxanthen-3-ones are reliably prepared by a one-pot protocol using alkali peroxosulfates in the key step. NMR spectra in deuterated sodium hydroxide confirm the anticipated structures and allow the determination of the dye contents by an internal standard. Georg Thieme Verlag Stuttgart.
- Schrick, Petra,Geick, Klaus,Waldvogel, Siegfried R.
-
experimental part
p. 2211 - 2216
(2009/04/06)
-
