Verfahren zur Herstellung von im Isopropylrest chlorierten Isopropylarylverbindungen

• Main Authors: (SCHWEIZ) CHARLES GRAENACHER, RIEHEN, RIEHEN MAX GEIGER, BASEL EDUARD USTERI
• Format: Patent
• Language: German
• Published: 05.06.1952
• Subjects: ACYCLIC OR CARBOCYCLIC COMPOUNDS; CHEMISTRY; METALLURGY; ORGANIC CHEMISTRY

Chloro-isopropylaryl compounds of formula CX2Cl.CRZ.CX2Cl, where R is aromatic which may be substituted by alkyl, alkoxy or halogen, Z is as R or is chlorine, and one or two of the groups X are chlorine and the rest are hydrogen, are prepared by treatment of a chlorinated acetone of formula CX2Cl.CO.CX2Cl with an aromatic compound RH in the presence of aluminium chloride. With aromatic compounds such as benzene, ethylbenzene, chlorobenzene, or o-dichlorobenzene a product is usually formed in which Z is chlorine; when the aromatic compound is, e.g., o-xylene, naphthalene or anisole, Z in the product is usually the same as R. The chlorinated acetone may be a mixture of isomers. The reaction temperature is low, e.g., in the range - 15 DEG C. to + 5 DEG C. In the examples, in all of which aluminium chloride is used, (1) 1 : 1 : 3-trichloroacetone is treated with chlorobenzene to give tetrachloroisopropyl - p - chlorobenzene; 1 : 1 : 3 : 3 - tetrachloroacetone is treated with, (2) chlorobenzene to give symmetrical pentachloroisopropyl-p-chlorobenzene; (4) toluene to give pentachloroisopropyltoluene; (5) and (6) anisole to give pentachloroisopropylanisole; and (7) a -chloronaphthalene to give pentachloroisopropyl-a -chloronaphthalene; and (3) 1 : 1 : 1 : 3-tetrachloroacetone is treated with chlorobenzene to give asymmetrical pentachloroisopropyl - p - chlorobenzene. The Specification as open to inspection under Sect. 91 comprises also the compound 2 : 4-dichlorotoluene as a suitable aromatic compound, and states that pentachloroisopropyl-p-chlorobenzene treated with alkali gives tetrachloroisopropenyl - p - chlorobenzene. This subject-matter does not appear in the Specification as accepted.