METHOD OF PRODUCING SUBSTITUTED 7,8-DICYANOPYRIMIDO[2,1-b][1,3]BENZOTHIAZOLES Russian patent published in 2014 - IPC C07D513/04 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing substituted 7,8-dicyanopyrimido[2,1-b][1,3]benzothiazoles of general formula (I)

where a R=CH₃, R₁=C₆H₅; b R=CH₃, R₁=4-CH₃OC₆H₄; c R=CH₃, R₁=2-thienyl; d R=C₆H₅, R₁=4-CH₃OC₆H₄. The method is carried out by reacting 4-bromo-5-nitrophthalonitrile with esters of 2-thioxo-1,2,3,4-tetrahydropyrimidine-5-carboxylic acids in the presence of triethylamine, which is used as a deprotonating agent. The reaction takes place at temperature of 18…35°C and molar ratio of reactants (1):(2):(TEA)=1:1:2, for 12-30 hours in dimethylformamide solution. Further, the reaction mass is diluted with water, the water being in tenfold excess, at temperature T=0…25°C; the tarry residue released is decanted from the aqueous layer and recrystallised from alcohol; the precipitate of the end product is filtered and dried on air.

EFFECT: synthesis of compounds which are used as precursors for producing phthalocyanines.

1 tbl, 4 ex