Patent GB-822009-A (GB)
Title: Manufacture of new aromatic compounds containing fluorinated side chains
IPC: C07C205/12
Filed: 1955-09-12
Abstract: Azo dyestuffs may be prepared from components containing one or more tetrafluoroethyl substituents.  Thus a red dyestuff is obtained by diazotizing tetrafluoroethylaniline and coupling with 8-acetylamino-1-naphthol-3 : 6-disulphonic acid.ALSO:The invention comprises aromatic compounds (other than tetrafluoroethylbenzene) containing, directly bound to the nucleus, one or more tetrafluoroethyl groups and/or one or more chains of tetrafluoroethylene units terminated by an hydrogen atom (in particular, compounds of the general formula <FORM:0822009/IV (a)/1> wherein A represents an aromatic system, each R represents hydrogen, an alkyl, aryl, ether, thioether, tetrafluoroethylene, carboxylic or sulphonic acid, ester or amide, nitro, amino, hydroxy, mercapto or phosphonic acid group or a halogen atom or quinonoid oxygen atom, x is 3 when A is a benzene residue, 5 when A is a naphthalene residue and 7 when A is trinuclear, m is a whole number and n and o are each zero or a whole number), and a method of preparing them and tetrafluoroethylbenzene by the reaction between tetrafluoroethylene and an aromatic compound in presence of one or more cobalt carbonyl compounds at raised temperature under superatmospheric pressure.  In examples, tetrafluoroethylene reacts with benzene, toluene, naphthalene, anisole, p-dichlorobenzene, benzoic acid methyl ester, para-xylene, tetrafluoroethylbenzene, tetrafluoroethyltoluene, acetophenone, 1 : 3 - dimethoxybenzene, chlorobenzene, diphenyl, phenyl sulphide, and 1 : 2 : 3 : 4-tetrahydronaphthalene in presence of cobalt carbonyl and water gas, dicobalt carbonyl, dicobalt octacarbonyl or Co(CO)4, to give products including tetrafluoroethyl benzene, tetrafluoroethyltoluene, a - and b -tetrafluoroethylnaphthalene, tetrafluoroethylanisole, tetrafluoroethyl - para - dichlorbenzene, tetrafluoroethylbenzoic acid methyl ester, 2-tetrafluoroethyl - 1 : 4 - xylene, bis - tetrafluoroethylbenzene and octafluorobutylbenzene, polytetrafluoroethylbenzenes and isomers with longer polyfluoralkyl side chains, tris-tetrafluoroethylbenzenes and isomers, octafluorobutyltoluene, bis - tetrafluoroethylnaphthalenes, tetrafluoroethylacetophenone, tetrafluoroethyl - 1 : 3 - dimethoxybenzenes, 1-chloro-2-, 3- and 4-tetrafluoroethylbenzenes, tetrafluoroethyldiphenyls, tetrafluoroethylated phenyl sulphides and tetrafluoroethyl - 1 : 2 : 3 : 4 - tetrahydronaphthalenes; tetrafluoroethylbenzene is nitrated and the nitrated product reduced to give m-tetrafluoroethylaniline; tetrafluorethyltoluene is nitrated to give mono- and di-nitro products and these reduced to the corresponding amines; octafluorobutylbenzene gives a nitro and amino product; acetanilide is tetrafluoroethylated and the product hydrolysed to tetrafluoroethylaniline; o - chlorotetrafluoroethylbenzene is nitrated to 1 - chloro - 2 - tetrafluoroethyl - 4 and -6-nitrobenzene; a mixture of m- and p-chlorotetrafluoroethylbenzene is nitrated and the product separated into 1-chloro-2-nitro-4-tetrafluoroethylbenzene and 1-chloro-x-nitro-3-tetrafluoroethylbenzene.  Many other hydrocarbons and substituted hydrocarbons suitable for the reaction are specified. Other reactions which may take place after the introduction of the polyfluoroalkyl groups are oxidation of alkyl substituents to carboxylic acid groups, which may be esterified or amidated, as also may sulphonic acid groups; hydrolysis of ester groups, and of ether and thioether groups to hydroxy and mercapto groups; oxidation of suitably substituted aromatic compounds to quinones.