Ciatyl,Tropon,W. Germany,1961
A mixture of 31 5 g (0.1 mol) of 2-chloro-9-(3'-dimethylaminopropylidene)-
thiaxanthene (MP 97°C) and 100 g of N-(β-hydroxyethyl)piperazine is heated
to 130°C and boiled under reflux at this temperature for 48 hours. After
cooling,the excess of N-(β-hydroxyethyl)piperazine is evaporated in vacuo,
and the residue is dissolved in ether. The ether phase is washed with water
and extracted with dilute acetic acid, and 2-chloro-9-[3'-N-(N'-β-
hydroxyethyl)piperazinylpropylidene]-thiaxanthene separated from the
aqueous acetic acid solution by addition of dilute sodium hydroxide solution to
basic reaction. The free base is extracted with ether, the ether phase dried
over potassium carbonate, the ether evaporated and the residue dissolved in
absolute ethanol. By complete neutralization of the ethanolic solution with a
solution of dry hydrogen chloride in absolute ethanol, the dihydrochloride of 2-
chloro-9-[3'-N-(N'-β-hydroxyethyl)piperazinylpropylidene]-thiaxanthene is
produced and crystallizes out as a white substance melting at about 250°C to
260°C with decomposition. The yield is 32 g.