Ethanol → HCID 131711802, compound

Participants

Reaction Conditions

Reaction Steps

927 parts of anthracene-9-aldehyde are suspended in 4.2 liters of ethanol. The suspension is treated with 10 parts by volume of piperidine and at about 45° C. over the course of one hour with 310 parts of malonic acid dinitrile in 400 parts by volume of ethanol. The orange suspension is stirred for 2 hours at 70° C. and subsequently cooled to 5°-10° C. The suspension is filtered with suction and the residue is washed with 500 parts by volume of ethanol and dried in vacuo at 90°-100° C. to yield 1077 parts of the intermediate of the formula ##STR22## 254 parts of the resulting intermediate are finely suspended in 1.75 liters of dry benzene. At room temperature, 320 parts of anhydrous aluminium chloride are added thereto over the course of about 2 hours. The green suspension is heated to 80° C. over the course of 45 minutes, stirred for 15 minutes at this temperature and then allowed to cool to 10° C. The benzene is decanted off from the viscous mass and the residue is poured onto 7 kg of ice. The aqueous suspension is stirred for 8 hours at room temperature. The suspension is filtered off and the residue is washed neutral with about 2 liters of water and dried in vacuo at 105° C. to yield 254 parts of 2-cyano-3-aminobenzanthrone. The compounds of the formula ##STR23## wherein R4 represents a halogen atom, a lower alkyl group or hydrogen, are ordinarily accessible by reaction of the vinylidene compounds of the formula ##STR24## with Friedel-Crafts reagents, wherein treatment is effected in inert solvents such as benzene, nitrobenzene or carbon disulphide at -20° C. to 150° C., preferably at 0° C. to 100° C., with ferric trichloride, boron trifluoride, boron trifluoride etherate or preferably aluminium chloride, and processing is carried out in the conventional manner.

Provenance & Evidence