Patent GB-1102692-A (GB)
Title: Fluorinated aromatic compounds
Inventor: TATLOW JOHN COLIN
IPC: C25D3/10
Filed: 1964-03-03
Abstract: Compounds of the formula:-Z(CF2)n - (L) - C6F4 - Y, in which Z is H, F or CI; Y is -OH, -SH, -COOH, -SO3H, -OM, -SM, -COOM, -SO3M, -NH2 or -NHNH2, M being an alkali metal, n is an integer from 1 to 13, L is -CF2- or -CH2O- and -C6F4-is a tetrafluorophenylene group are surface-active agents which may be used to produce a foam blanket on top of an electro-plating solution, especially a chromium-plating solution.  In an example compounds of the formula <FORM:1102692/C6-C7/1> in which (a) R is perfluoropropyl and Q is -OH; (b) R is perfluorobutyl and Q is -OH, (c) R is perfluorobutyl and Q is -SO3H and (d) R is H (CF2)6 - CH2O- and Q is OH are added to a chromium-plating solution containing chromic acid and sulphuric acid to produce a foam blanket on top of the solution.ALSO:The invention comprises fluorinated aromatic compounds of formula Z(CF2)n-(L)-C6F4-Y in which Z is H, F or Cl; Y is -OH, -SH, -COOH, -SO3, -OM, -SM, -COOM, -SO3M, -NH2 or NHNH2, M being an alkali metal; n is an integer from 1 to 13; L is -CF2-or -CH2O-; and -C6F4- represents a tetrafluoro phenylene group.  The compounds may be prepared by introducing the polar group Y into the compound Z(CF2)n-L-C6F5 by known methods.  The compound of formula Z(CF2)n-CF2-C6F5 is prepared by reacting sulphur tetrafluoride with the phenone Z(CF2)n-CO-C6F5 which in its turn may be prepared by the oxidation of Z(CF2)n-CHOH C6F5.  The latter compound is obtained by the reaction of the compound Z(CF2)nCHO with a Grignard reagent C6F5MgBr.  Alternatively, the phenone may be prepared by the action of the Grignard reagent on the acid chloride Z(CF2)nCOCl which may be prepared by the action of PCl5 on Z(CF2)nCOOH, or by the direct reaction of Z(CF2)nCH2OH with C6F6 under basic conditions.  In the examples: (a) heptafluorobutyraldehyde is prepared by reacting heptafluorobutyric acid with lithium aluminium hydride to produce heptafluorobutyraldehyde which is dehydrated with phosphorus pentoxide; the heptafluorobutyraldehyde is then reacted with pentafluorophenyl magnesium bromide and the resulting compound treated with sulphuric acid to give pentafluorophenyl heptafluoropropyl carbinol; this carbinol is then oxidized with chromium trioxide to give perfluorobutyrophenone; the phenone is then reacted with sulphur tetrafluoride to give perfluorobutylbenzene the perflurobutylbenzene is then reacted with sodium hydrosulphide to give p-perfluorobutylthiophenyl which is then reacted with chlorine and hydrogen peroxide to give p-perfluorobutylbenzene sulphonyl chloride which on hydrolysis with potassium hydroxide gives potassium p-perfluorobutylbenzene sulphonate; an alternative method of preparing the perfluorobutyrophenone by reacting the Grignard reagent referred to above with heptafluorobutyrylchloride is described; (b) sodium 1H, 1H, 7H-dodecafluoroheptanoxide is reacted with hexafluorobenzene to give 1H, 1H, 7H-dodecafluoro-n-heptyl-pentafluorophenylether which is treated with potassium hydroxide and then acidified to give dodecafluoroheptyl - 4 - hydroxytetrafluorophenyl ether. The new compounds are surface-active agents and may be used as additives for electroplating baths.