Патент USA US2610977код для вставки
2,610,969 ii’atented Sept. 16, 4.1952 UNITED ,sTA-TEs i . 2,610,969 PRODUCTION or 111mm. PYRAZOLINES mi. Dam main and George Frank Du?m'. 'Ilford, England,_ assignors to Ilford‘ Limited, I‘lford, England, a British company - - No Drawing. Application May 29, 1950, Serial No.7, > - a 165,117. In Great Britain June 3,1949 ' _ 30mins‘. (crate-731p); solved in 2.5 parts‘ byfvolume ‘of concentrated hy drochloricacid and 2.5 parts‘ of'water. cooled to I > This invention relates to the production of di arylpyrazolines, .‘1 ,' ' . . . If a‘ l-‘aryl'pyrazoline is-ooupled in acidsolu tion with a diazonium salt of an aromatic amine, an azo dye is obtained and this is believed to be a 3-arylazo-l-arylpyrazoline. It has now been dis covered, however, thatii the reaction is carried out in a basic medium the main product formed is a 1:3-diaryl pyrazoline. According to the present invention, therefore, 5° C. and diazotised by the addition of an aqueous solution of. 0.7 .part by weight‘of sodium nitrite. The solution was added to‘a vstirred solutionof 1.6 parts by weight of '1;-m-.tolyl_ pyrazoline in 10 parts by ‘volume of pyridine.‘ After standingvfor onehour the mixture was diluted with 100 parts oflwaterf and the solid‘removed by ?ltration; The productjwas puri?ed by recrystallisation from methyl _ alcohol to give yellow plates. , M. pt. a process for the production of 1:3-diaryl pyraz olines comprises reacting in a basic medium a l-aryl pyrazoline with a diazonium salt prepared from a primary arylamine. Conveniently the re action may be effected in aqueous pyridine or al coholic alkali. ‘ ; ' The reaction is‘somewhat surprising since'azo dye formation u'suallyoccurs when azo‘ dye com ponents are coupled‘in alkaline media. . The process of the present invention is believed to follow the equation: CH2 illryll 120° C.‘ ' ' > EXAMPLEG' p l ' . , ‘ j , ‘ Preparation of 3ephenyl1+(m-tolyllpwazolia ~,1.1,8 parts by volume of anilinewere dssolved in 3 parts by volume of concentrated hydrochloric acid and 3 parts of water, cooled to 5° C., and di azotised by the addition of an aqueous solution of 0.93 part by weight of sodium nitrite. This solu tion was added to a stirred solution of 2.00 parts by weight of l-m-tolyl pyrazoline in 14 parts by volume of pyridine while maintaining the tem perature between 0° and 5° C. After standing for CH2 one hour the mixture was diluted with 100 parts of water when a reddish oil was precipitated. The Aryll oil solidi?ed on treatment with methyl alcohol and the solid was recrystallised from methyl al cohol to give yellow crystals. M. pt. 885° C. V and the nitrogen can be observed to bubble away from the reaction mixture. In the foregoing 30 EXAMPLE 4 formulae the aryl groups may be, for example, Preparation of I-phenyl 3-(m-tol1/Dpyrazolme phenyl or naphthyl groups, or aryl groups carry ing alkyl, aralkyl, aryl, nitro, alkoxy, hydroxy, 1.09 parts by volume of m-toluidine were dis ‘ hydroxyalkyl, carboxylic or sulphonic groups, or solved in 2.5 parts by volume of concentrated hy halogen atoms. The aryl group in the l-posi drochloric acid and 2.5 parts of water, cooled to tion can also be substituted by amino or sub 5° C. and diazotised by the addition of an aqueous solution of 0.‘? part by weight of sodium nitrite. stitutedamino groups. ‘ The acid HX is absorbed by the basic medium The following examples will serveto illustrate the invention: The solution was added to a stirred solution of 1.48 parts by weight of l-phenyl pyrazoline in 10 parts by volume of pyridine. After standing for ' EXAMPLE 1 Preparation of 1:3-diphenyl pyrazolme one hour the mixture was diluted with 100 parts of water and the solid removed by ?ltration. The 0.93 part by weight of aniline was dissolved in 2.5 parts by volume of concentrated hydrochloric product was puri?ed by recrystallisation from M. pt. methyl alcohol to give yellow crystals. acid and 2.5 parts of water, cooled to 5° C. and 45 diazotised by the addition of an aqueous solution of 0.7 part by weight of sodium nitrite. The 77° 0. solution was added to a stirred solution of 1.45 Preparation of i-phenyl 3-(p-bromophenyD EXAMPLE 5 parts by weight of l-phenyl pyrazoline in 10 parts by volume of pyridine while maintaining the tem 50 perature between 0° and 5° C. After standing for one hour the mixture was diluted with 100 parts pyrazoline . 3.42 parts by weight of p-bromoaniline were dis solved in 5 parts by volume of concentrated hydro of water and the product removed by ?ltration. It was puri?ed by recrystallisation from ethyl alcohol to give very pale yellow needles. M. pt. chloric acid and 10 parts of water, cooled to 5° C. and diazotised by the addition of an aqueous solu 152° C. solution was added to a stirred solution of 2.9 EXAMPLE 2 Preparation of 1 :3-di- (m-tolyl) pyrazoline 1.09 parts by volume of m-toluidine were dis tion of 1.4 parts by. weight of sodium nitrite. The parts by weight of l-phenyl pyrazoline in 20 parts by volume of pyridine while maintaining the tem perature between 0° and 5° C. After standing 60 for one hour the mixture was diluted with 200 2,610,969 parts of water and the solid removed by ?ltra tion. The product-was puri?ed‘by-recrystallisae tion from-methyl alcohol to give small light yel low plates. M. pt. 130° C. EXAIVIPLE 6 Preparation of I-phenyl S-(p-suZphopIienyDpy- _ razoline' 1.73 parts by weight of sulphanili'ci acid'vwerer dissolved in 2.5 parts by volume of concentrated‘v hydrochloric acid and 5 parts of? water; cooled-to; 5° C. and diazotised by the addition-ortin-aqueousR 4 and are of use where compounds having such properties; are of .value, e. g.; as textile‘; whitening agents’ as described in- co-pending application Serial No. 165,116 ?led on even date herewith. What we claim is: 1. Process» for the production of 1:3-diaryl pyrazolines which comprises reacting in a basic mediumi'a; 1_-aryl:pyrazoline wherein the 3-posi tion- is‘ unsubstituted, with a diazonium salt of a. . primary arylamine: 2: Process: for the production of 1:3-diaryl pylazolines, which comprises reacting in aqueous solution of 0.7 part by weight of sodium- nitrite; - _ pyridine a l-aryl pyrazoline wherein the 3-posi This solution was added'with stirring to a solu tion- is~ unsubstituted. with a diazonium salt of tion-oi 1.46 parts of l-rphenyl pyrazoline‘ in .10 parts; by volume of, pyridine: while“ maintaining the temperature between'ftrf and"? CI A?’er standing. one 110111",t11'e mixture was". diluted ‘with a primary arylamine. 3lzProcessz for‘ tliezproductiomot: lz?sdiaryl pyrazolines which comprises reactingi'imthepreae ence;ofialcoliolicalkaliza,learylrpymwlinewhere imthe ‘3epositi0n'. issunsubstitutedi. with; a" dine by volume‘ of‘ concentrated; hydrochlori'o'aeid. 20 zoniumasalti of sriprimary'arylaminezp strong, salt" solution was~ then. added" when a; yel low‘ solid was precipitated? The~ mixture‘: was GEORGE‘FRANK,DUFFIN:; JOHNTDAVID cooled in‘ ice, ?lteredlan‘d' the‘ solid, washed‘ with water; The: product was ?nally? puri?ed‘ by'rea crystallisation‘ from. water. containing :som‘eiani R-EFERENGES: CITED‘ I mal charcoal to givev small buiT-colouredlpl‘ates; The following’ references‘ are of record? inl the M. pt. 300° C. ?le oft-his patent‘: ' e ' The 1:3-diaryl pyrazolines: produced by the 50 ' parts‘ of ‘water; stronglyacidi?ed'with 20*parts process of thisinventionare in many- cases. en Chem; Abstl, vol"; 32,: p.. 1667?.“ (1‘938)1',_ citing tirel'y new compounds, and’ such new‘ compounds 30 Jacob etall, Jr..Chem.. Society-- (liond'omi 1937, pp. 1929-1931; ~ 1 , per‘ se' form part of this invention.- In: general Chem. Abstm vol. 41, p.v1221,wcitihg41’ani_zzi the‘. compounds‘ exhibit? 'a- strong" violet; or; lilue Gazz. Chim. ital‘ 73L .pp..3'35.'-343T'( 195101, ?uorescence'in; daylightl or: ultras-violet lights-mi a1 lesser“ ?uorescence? in oniinameiect'nlcl light, Beil'stein,_Vierte Au?auge, I-l'andliucli den Qr ganischen Chemie,‘ voll. 23,. pp.- 153 andi16'8‘.