Esucos,UCB Chemie,W. Germany,1962
To a suspension of sodamide in liquid ammonia and made from sodium in
liquid ammonia, there is added fractionally and with stirring phenothiazine.
After an hour there is added thereto, while maintaining the stirring, 1-chloro-
2-methyl-3-bromopropane, then 700 cc of toluene. The ammonia is then
driven off and heating under reflux is carried out for one hour.
After cooling, water is added and the solution then decanted. The toluene
phase is then evaporated in vacuo to constant weight. The residue is
constituted of 10-(2-methyl-3-chloro-propyl)-phenothiazine containing acertain quantity of phenothiazine which has not reacted. As this product is not
readily soluble in petroleum ether, it is possible to eliminate it by extraction by
means of this solvent.
By operating in this manner 10-(2-methyl-3-chloro-propyl)phenothiazine is
obtained. A mixture of l0-(2-methyl-3-chloro-propyl)phenothiazine and 1-[2-
(2-hydroxyethoxy)ethyl]piperazine is then heated at 110°-120°C for 20 hours.
After cooling, the reaction product is dissolved in 200 cc of benzene and the
solution washed several times with water.
The benzene phase is then extracted by dilute hydrochloric acid. The acid
aqueous phase is decanted, it is made distinctly alkaline and then extracted
with benzene. The benzene extract is dried and evaporated in vacuo. The
condensation product could not be crystallized. It may be converted into the
dihydrochloride which, after recrystallization from isopropanol, melts at 192°C.