Apegmone,Oberval,France,1978
(a) 1-para-chlorophenyl-3-(5'-chloro-2'-thienyl)-2-propen-1-one - (a) This
new compound was prepared in the following manner:
4.4 g of NaOH, in solution in 40 ml of water and 20 ml of ethanol, are cooled
to 120°C, and then there are successively added at this temperature 13.2 g
(0.086 mol) of para-chloroacetophenone and 12.6 g of 5-chlorothiophene-2-
aldehyde. The solution is left standing for 3 hours while stirring at ambient
temperature and the precipitate which has formed is centrifuged off,
whereafter it is washed with water and recrystallized from alcohol. Yield: 18.4
g, i.e., 75.7% of product, melting at 134°C.
(b) The ketone prepared according to a is condensed at the rate of 14.15 g
(0.05 mol) with 8.9 g (0.055 mol) of 4-hydroxycoumarin in 80 ml of water in
the presence of 42 mg of hexamethyleneimine. Heating takes place for 4
hours under reflux and, after recrystallization, first of all from a mixture of
acetone and water and then from benzene, there are obtained: 12.6 g of 3-
(4'-hydroxy-3'-coumarinyl)-3-(5''-chloro-2''-thienyl)-parachloropropiophenone,
melting at 162°C (sealed tube).
(b) 4.45 g (0.01 mol) of 3-(4'-hydroxy-3'-coumarinyl)-3-(5''-chloro-2''-
thienyl)-parachloropropiophenone, in solution in 75 ml of isopropanol, are
reduced with 6.12 g (0.03 mol) of aluminum isopropylate, introduced while
stirring and in small quantities at ambient temperature.
The solution is refluxed for one hour and after cooling it is poured into 250 ml
of ice and 15 ml of concentrated HCl. On standing, a white precipitate is
obtained, which is centrifuged, washed with water, taken up in methanol and filtered.
5 volumes of water are added to this solution, and it is allowed to crystallize
at ambient temperature.
The product is analytically pure and shows a pasty fusion at 104°C (sealed
tube). Yield: 89%.
