Patent GB-629482-A (GB)
Title: Improvements in or relating to the production of heterocyclic nitrogen compounds
IPC: C07D417/04
Filed: 1947-03-19
Abstract: Acyloxypyrazoles of the formula:  <FORM:0629482/IV (a)/1> where Y is -CO- or -SO2-, RY- is acyl, R1 and R2 are organic groups, at least one of Z and Z1 is -COX or -SO2X (X = halogen) and the other may be hydrogen, are reacted with polyvinyl alcohol or its aminobenzaldehyde acetals, or with salicylic acid-formaldehyde resins to give high molecular weight colour formers or dye intermediates.ALSO:Acid halides of 5-acyloxypyrazoles are prepared by reacting a 5-pyrazolone, containing in at least one of the 1- and 3-positions a grouping containing a carboxylic or sulphonic acid radicle, with an acylating agent which contains no group capable of reacting with an acid halide radicle, and then converting the carboxyl or sulphonic group to a carbonyl or sulphonyl halide group by treatment with phosphorus pentachloride, trichloride or oxychloride, or thionyl chloride, or a correspoinding bromide to any of these.  The grouping joining the carboxyl or sulphonic radicle to the pyrazolone may be aliphatic, heterocyclic, or aryl, preferably the latter, e.g. benzene.  Specified groupings include ethylene, phenylene, benzylene, thiodiphenylene, sulphonyldiphenylene, pyridylene, thienylene, furylene and cyclohexylene.  These groups may be joined together by oxygen, sulphur, sulphonamido, carbonyl, sulphonyl, or acid amide links, and they may be substituted by alkoxy, chlorine, bromine, nitro, acylamido, alkyl, e.g. methyl or ethyl, or aryl, e.g. phenyl or naphthyl.  A preferred class of products is one containing a grouping in one of the 1- or 3-positions of the pyrazole containing a carbonyl or sulphonyl chloride radicle, and when the other position contains a group such as alkyl, e.g. methyl, ethyl, dodecyl, or hexadecyl; aryl, e.g. phenyl or naphthyl; or aralkyl, e.g. benzyl; or a substituted radicle of this type, e.g. chlorophenyl, nitrophenyl, b -ethoxyethyl, b -phenoxyethyl, trichloromethyl, and carbethoxymethyl. Still more preferred is the case when there is a grouping in the 1-position containing a carbonyl or sulphonyl chloride radical, there is a methyl group in the 3-position, and where in the 5-position there is the group R4-Y-O-, where Y is carbonyl and R4 is alkyl of 1-3 carbon atoms, alkoxyl of 1-3 carbon atoms, or phenyl, methylphenyl or ethylphenyl.  The acid chlorides may be converted to fluorides with, e.g., silver fluoride, or to iodides with, e.g., hydrogen iodide.  Many suitable starting materials and final products are specified.  In the examples: (1) 1-(41-carboxyphenyl)-3-methyl-5-pyrazolone in aqueous potassium hydroxide is treated with ethyl chlorocarbonate to give 1 - (41 - carboxyphenyl) - 3 - methyl - 5-pyrazolyl ethyl carbonate, which on treatment with thionyl chloride gives 1-(41-chloroformylphenyl) - 3 - methyl - 5 - pyrazolyl ethyl carbonate; (2) 1 - (41-sulphophenyl) - 3 - methyl - 5 - pyrazolone in alkali solution with benzoyl chloride gives the potassium salt of 1-(41-sulphophenyl)-3-methyl-5-pyrazolyl benzoate, which on treatment with phosphorus pentachloride and oxychloride gives 1 - (41 - chlorosulphophenyl)-3-methyl-5-pyrazolyl benzoate; (3), (4), (6) and (7) describe similar preparations; (5) p-carboxyphenylhydrazine hydrochloride is treated at pH 7.0-7.5 in aqueous solution with ethyl benzoylacetate to give 1-(41-carboxyphenyl)-3-phenyl-5-pyrazolone, which, refluxed with acetic anhydride, gives 1-(41-carboxyphenyl)-3-phenyl-5-pyrazolyl acetate, treatment of which with thionyl chloride gives 1-(41-chloroformylphenyl)-3-phenyl-5-pyrazolyl acetate.  Dye intermediates are prepared by reaction of these acyloxypyrazoles with any compound containing an amine, phenol, alcohol, or actine methylene group, e.g. phenol, aniline, p-chlorophenol, ethanol, deacetylated chitin.ALSO:Azo dyes are prepared by coupling di-azonium salts with the reaction product of a compound containing an amine, phenol, alcohol or active methylene group (e.g. aniline, ethanol, phenol), with an acyloxypyrazole of the formula <FORM:0629482/IV (c)/1> where Y is -CO- or -SO2-, RY- is acyl, R1 and R2 are organic groups, at least one of Z and Z1 is -COX or -SO2S (X is halogen) and the other may be hydrogen.  These azo dyes may be used to dye rayon, nylon, and cellulose acetate fibres.