DE3245200A1 - Azolylstyryl compounds - Google Patents

Abstract

The invention relates to compounds of the formula <IMAGE> or their isomer mixtures, in which A represents a quasiaromatic heterocyclic radical, B represents a radical of the formula <IMAGE> n represents 0, 1, 2 or 3, preferably 0-2, R1 represents hydrogen, CN, R or acyl, R2 represents hydrogen, halogen, -OR, -NHR, -N(R')2 or NHCOR, R' represents alkyl and R represents R', alkenyl, aralkyl, cycloalkyl or aryl. They are useful optical brighteners and/or laser dyes and in some cases intermediates for the preparation of these final products.

Description

Azolyl styryl compounds

The invention relates to compounds of the formula or their isomer mixtures, in which A is a quasi-aromatic heterocyclic radical, for a radical of the formulas n only u, -i, 2 or more, preferably uz, R1 for hydrogen, CN, R or -SO2R, -COR, COOR, -CONHR, -CON (R ') 2 R2 for hydrogen, halogen, -OR, -NHR ; -N (R ') 2 or NHCOR, R' for alkyl and R for R ', alkenyl, aralkyl, cycloalkyl or aryl, where A, B, R' and R are further non-chromophoric substituents customary in the chemistry of optical brighteners can wear, as well as their use as optical brighteners or laser dyes.

Suitable quasi-aromatic heterocyclic radicals A are radicals 5- or 6-membered 1- to 3-ring heterocycles, such as those of the oxazole, Imidazole, 1,2,4-oxadiazole, 1,3,4-oxadiazole, 1,3,4-thiadiazole, 1,2,3-, 1,2,4- and 1,3,4-triazole, pyrimidine, 1,3,5-triazine, benzoxazole, benzthiazole, benzimidazole, Naphthoxazole, benzo-s-triazole, naphtho-s-triazole, benzo (b) -furan-, quinazoline- or quinoxaline series, which are linked to the rest of the molecule in the usual way are.

Particularly preferred are those of the benzoxazole, benzo (b) furan, Benzo-s-triazole, naphtho-s-triazole, 1,2,4- and 1,3,4-oxadiazole, 1,2,3-, 1,2,4- and 1,3,4-triazole and 1,3,5-triazine series.

Suitable non-chromophoric substituents are R, OH, CN, OR, COR, SO2R, NHCOR, CONH2, NHSO2R, OCOR, COOR, COOH, NHR ', SO3H and others

Alkyl is in particular C1-C6-alkyl, which is replaced by hydroxy, C1-C4-alkoxy, CN, carboxy, C1-C4-alkoxycarbonyl, CONH2, chlorine or bromine can be substituted or trifluoromethyl.

Alkenyl is especially C2-C5-alkenyl.

Halogen is in particular fluorine, chlorine and bromine, preferably chlorine.

Cycloalkyl is preferably cyclohexyl one to three times, for example can be substituted by methyl or chlorine.

Aryl is in particular optionally by C1-C4-alkyl, trifluoromethyl, Substituted chlorine, bromine, carboxy, cyano, C1-C4-alkoxycarbonyl or C1-C4-alkoxy Phenyl.

Aralkyl is especially phenyl-C1-C4-alkyl, which is still in the phenyl nucleus can be substituted by chlorine, methyl or methoxy.

Preferred compounds are those of the formula I in which A represents a 1,2,4-oxadiazole, 1,3,4-oxadiazole, 1,2,3-triazole, an optionally substituted by 1-2 C1-C4-alkyl , C1-C4-alkoxy, 1-2 chlorine, benzyl, phenyl, cyclohexyl, C1-C4-alkylsulfonyl or C1-C4-alkoxycarbonyl-substituted benzoxazole, benzo (b) furan, benzo-s-triazole, naphtho-s -triazole, 5-phenyl-1,3,4-oxadiazole, 5-phenyl-1,2,4-oxadiazole, or 3-phenyl-1,2,4-oxadiazole radical and B for a radical of formula (or mixtures of the two), where R1 is hydrogen, allyl, C1-C4-alkoxycarbonyl, an alkyl radical optionally substituted by hydroxy, acetoxy, C1 -C4 -alkoxy, phenoxy, chlorine, cyano, sulfo or CF3, or an optionally substituted by C1-C4-alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, cyano or chlorine-substituted benzyl or benzoyl radical.

Particularly preferred radicals A are the benzoxazolyl-2-, benzo (b) furanyl-, 1,2,4- or 1,3,4-oxadiazolyl, naphtho-triazolyl and the benzo-S-triazolyl-2 radical.

Another group of preferred compounds are those of the formula I in which A has the preferred meaning mentioned above and B is a radical of the formula where R2 is hydrogen, chlorine, amino, C1-C4-alkylamino, phenylamino or a radical of the formula - (OCH2CH2) -OW W hydrogen, C1-C6-alkyl, benzyl, cyclohexyl or phenyl which is optionally substituted by chlorine or cyano, and m represent an integer from 0 to 7.

Another group of preferred compounds are those of the formula I in which A has the preferred meaning mentioned above and B for the remainder of the formula in which R1 is hydrogen, C1-C4-alkyl or phenyl which is optionally substituted by hydroxy, C1-C4-alkoxy, chlorine, cyano, C1-C4-alkoxycarbonyl or phenyl.

Particularly preferred compounds are those of the formula (I) in which A is the remainder of the formula B for the rest of the formulas where n = 1 and where V1 is hydrogen, C1-C4-alkyl, cyclohexyl, C1-C4-alkoxy, chlorine, benzyl, phenyl, C1-C4-alkoxycarbonyl, C1-C4-alkylsulfonyl, V2 is hydrogen, C1-C4-alkyl , Chlorine or C1-C4-alkoxy, V 3 denotes hydrogen, C1-C4-alkyl or chlorine and V4 denotes C1-C6-alkyl, benzyl, cyclohexyl or phenyl optionally substituted by C1-C4-alkoxy, hydroxy, chlorine or cyano.

V4 very particularly preferably represent an unsubstituted C1-C4-alkyl radical such as methyl, ethyl, n-propyl, isopropyl or n-butyl; V1 for hydrogen, methyl, Chlorine; V2 and V3 for hydrogen.

The compounds of the formula (I) can be prepared by various methods known per se. A) a phosphono compound of the formula is preferably condensed where Z is a grouping of the formulas with an aldehyde of the formula or b) a phosphono compound of the formula with an aldehyde of the formula in organic solvents in the presence of basic condensing agents (cf., for example, DE-OS 2 525 684, 2 833 470 and 3 013 279).

Preferred radicals R are C1-C4-alkyl, cyclohexyl or phenyl.

The solvent chosen is advantageously inert, for example Hydrocarbons such as toluene or xylene or alcohols such as methanol, ethanol, isopropanol, Butanol, glycol, glycol ethers such as 2-methoxyethanol, hexanol, cyclohexanol, cyclooctanol, also ethers such as diisopropyl ether, dioxane, tetrahydrofuran, and formamides or N-methylpyrrolidone. Dipolar aprotic solvents are particularly suitable such as dimethylformamide and dimethyl sulfoxide.

Strongly basic compounds are suitable as condensing agents such as alkali and alkaline earth metal hydroxides, alkali and alkaline earth amides and alkali and Alkaline earth metal alcoholates, for example potassium hydroxide, sodium hydroxide, potassium tert-butoxide, Sodium amide or sodium methylate, also the alkali compounds of dimethyl sulfoxide and alkali hydrides and optionally alkali metal dispersions.

The temperature range from 0 to 1000 ° C. is preferably used.

The compounds of the formula I according to the invention can also be used in the Way to be prepared that one of the corresponding aldehydaniles in a dipolar aprotic solvents such as dimethylformamide in the presence of basic condensing agents with the corresponding methyl compounds.

While the compounds III and IV are generally known (cf. DE-OS 1,294,917, 2,148,014, 2,453,355, 2,709,924 and 2,926,234 as well as US-PS 3,351,591 and 4,142,044), the compounds are the formulas II and V (R1 / R2 # hydrogen) have not yet been described in the literature; these compounds are obtained in a manner known per se according to the following reaction scheme: The starting compounds (IIa) (B = 1,2,3,4-tetrazole radical) can be prepared by methods known per se by cycloaddition of sodium azide onto p-tolunitrile and subsequent reaction with appropriate halides (cf., for example, J. org. Chem. 15, 1082 (1950), J. org. Chem.

22, 1142 (1957), J. Amer. Chem. Soc. 80, 3908 (1958) and Can. journal of Chem. 47, 813 (1969)).

The starting materials (IIa) (B = 1,3,4-oxadiazole residue) can according to various processes known from the literature (cf.e.g. Gazz. chim. ital. 91, 866 (1961); Tetrahedron Letters 42 (1964) 3119 and Ann. 686 (1965) 145).

The condensation of amidoximes with chloroformic acid esters (cf. Ber. 18, 2465 (1885) and Ber. 19, 1481 (1886) and Ber. 18 2456 (1885) and Ber. 19, 1475 (1886)) and the subsequent reaction with corresponding halides in the presence of bases, the starting materials (IIa) or

also directly (II) (B = 1,2,4-oxadiazolinone-2-residue).

The starting materials (IIa) (B = 1,2,4-oxadiazole residue) are finally obtained in a manner known per se from the unsubstituted oxadiazolinone-2 compounds by chlorination and reaction with alcohols or amines (cf. e.g.

Bull. Soc. Chim. Belges 78 (1969) 41 and Bull. Soc.

Chim. Belges 78, 47 (1969).

A particularly advantageous process for the preparation of compounds of the formula I is characterized in that compounds of the formula with metal azides in polar organic solvents to form compounds of the formula converts this either a) optionally with compounds of the formula R1 -x in which X is halogen, to give compounds of the formula or b) optionally with compounds of the formula (T = Br, Cl) to compounds of the formula where B 'for In this preparation method, the compounds VIII can also be obtained in the form of isomer mixtures, depending on how the reaction is carried out, which can, if desired, be separated by customary separation methods (recrystallization, chromatography).

However, for the technical purposes specified below, a such separation is not required.

Only some of the compounds of the formula VI are known.

They are obtained in a customary manner, for example by reacting compounds of the formula with p-cyanobenzaldehyde (cf. DE-OS 24 53 355, DE-AS 1 052 405, JP-OS 49/85378).

The implementation of the tetrazole derivatives VII with the compounds R1X can in the temperature range from 0-1200C, preferably at 25-90 "C and the implementation of VII can be carried out with R2COT in the range of 50-1500C, preferably at 70-1200C.

Both reactions are in inert solvents for example Ethers such as dioxane, tetrahydrofuran, diisopropyl ether, and also in hydrocarbons such as toluene, xylene, chlorobenzene and 1,2-dichlorobenzene or in formamides such as dimethylformamide, Dimethylacetamide or dimethyl sulfoxide, preferably in the presence of acid acceptors, in particular tertiary organic bases such as triethylamine, dimethylaniline, pyridine, Dimethylaniline, or hexahydrodimethylaniline.

A particular process for the preparation of compounds of formula I wherein B is the remainder of the formula is characterized in that compounds of the formula I in which B is the remainder of the formula is rearranged in a polar solvent either in the presence of auxiliaries such as acids or bases or else without auxiliaries at temperatures between 100-2500C. The compounds of the formula I are obtained in good yields and in high purity.

The preparation of the compounds of the formula I in which V = hydrogen means, can finally also by reacting the compounds of the formula I in which V4 = C1-C4-alkyl means carried out with mineral acids in organic solvents.

Both inorganic bases can be used as bases in the process according to the invention as well as organic compounds that are sufficiently soluble in the reaction mixture, be used. Preferred bases are organic bases, e.g.

Triethylamine, N-methyl- or N-ethyl-piperidine, piperidine, pyrrolidine, 1,4-diazabicyclo / 2,2,27 octane (DABCO), morpholine, N-methyl or N-ethylmorpholine and N-ethylpyrrolidine or the like. Suitable polar solvents are higher-boiling ones Alcohols such as n-butanol, tert-butanol, glycol, diethylene glycol. Glycol ethers such as 2-methoxyethanol, 2-ethoxyethanol, nitriles such as benzonitrile, also formamides, N-methylpyrrolidone, Dimethyl sulfoxide and phosphoric acid amides. Dimethylformamide and dimethylacetamide are preferred and phosphoric acid tris-dialkylamides, where alkyl is in particular C1-C4-alkyl.

The reaction temperatures for the reaction according to the invention are expediently between 100 and 2500 ° C., preferably between 120 and 200 ° C.

The lightening of the fiber material with the aqueous or possibly organic Lightening liquor is carried out according to the dyeing process that is typical for the respective type of fiber.

Further, Conversions known per se are carried out, such as halogenations, functional Modifications of carboxyl groups, introduction of chloromethyl groups or exchanges of halogen atoms against cyano groups.

The compounds of formula I show in dissolved or finely divided Condition a very strong blue fluorescence. They are suitable individually or as mixtures for tinting a wide variety of organic materials white.

The following materials are, for example, the substrates to be lightened called: varnishes, natural or synthetic fibers, such as those made from natural or regenerated cellulose, acetyl cellulose, natural and synthetic polyamides, Polyesters, polyolefins, polyvinyl chloride, polyvinylidene chloride, polystyrene or Polyacrylonitrile and foils, films, tapes or moldings made from such materials.

The water-insoluble compounds according to the invention can be dissolved be used in organic solvents or in aqueous dispersion, advantageous be used with the aid of a dispersant.

The amount of the compounds to be used according to the invention of the general Formula I, based on the material to be optically brightened, can be used depending on the area of application and the desired effect vary within wide limits. You can easily through trials are determined and is generally between about 0.01 and about 2%.

Compounds of the formula I, especially those of the formula I with a Oxdiazolylrest, with their large quantum yield and high lightfastness can also still be used for tunable dye dissolvers in the blue spectral range from 400-480 nm. For this purpose, they are used in the arrangement as they in DE-OS 1 910 784 and GB-PS 1 255 399 is described.

Example 1 A suspension of 51.5 g (0.16 mol) of 4-cyano-4 '- (benzoxazol-2 "-yl) -stilbene, 11.4 g (0.175 mol) of sodium azide and 7.4 g (0.175 mol Lithium chloride in 850 ml of dimethylformamide is stirred for 25 hours at 130 ° C. It is adjusted to pH 3-4 with concentrated hydrochloric acid and filtered, washing with water and ethanol after drying in vacuo at 500 ° C. yields 60.6 g (94.8% of theory). Th.) The compound of the formula which can be recrystallized from dimethylacetamide.

(M.p .: 3210C dec., Max. 369 nm).

Example 2 To a solution of 11 g (0.03 mol) of compound (1) from Example 1 and 3.3 g (0.033 mol) of triethylamine in 120 ml of dimethylformamide are added 5.2 g (0.03 Mol) of benzyl bromide are added dropwise and the mixture is stirred for 3 hours at 90 ° C. After cooling to 250 ° C., the reaction mixture is mixed with 300 ml of water and the crystalline precipitate is filtered off. 8.5 g (62% of theory) of a 1,2- Mixture of isomers of the formula which can be crystallized from dimethylformamide (mp .: 249-51 ° C, #max: 36-0 nm). The compound provides excellent whitening effects on PES in the exhaust-HT process (130 ° C).

The compounds listed in the table below are also prepared analogously to the above example. No AR fluorescence in DMF II-J- 3 g SNJ H (2-) green. blue N 4 <N \ H (2-) blue purple 5 Cl¾Y CH2 - OCH3 rotst. blue N CH, COC HH (2-) blue C2H500Cu N JN \ ' LJ CH, CH, -CN red-violet 8 CH3OüÖ to N. -CH2-CH = CH2 neutral blue Ph 9 4 N -C-OC2H5 green. blue 0 No AR fluorescence in DMF Ph N 10 3) $$$ NN Õ blue-violet 11 C2HsSO $ »CN (C2Hs) 2 green. blue 0 12 H (2-) blue 12 XJTO # ~ H (2-) blue 13 ML H t2-) ro.tst. blue CH3 Example 14 11 g (0.03 mol) of the compound (1) from Example 1 and 7.1 g (0.07 mol) of triethylamine are stirred in 100 ml of dimethylformamide for 1 hour at 80 ° C. Underneath the surface of the solution then 3.3 g (0.03 mol) of ethyl chloroformate are added dropwise. The mixture is stirred for 2 hours at 80 ° C. and treated again with 3.3 g (0.03 mol) of ethyl chloroformate. After 2 hours at about 90 ° C., the mixture is heated to 100 ° C. The filtrate is concentrated in vacuo, the residue is treated with 50 ml of water and filtered off.

Drying in vacuo at 50 ° C. gives 8.5 g (69.1% of theory) of pale yellow crystals of the compound of the formula which can be recrystallized from chlorobenzene.

Mp. 209-2110C, absorption: λ max.: 364 nm. It provides brilliant White effects on PES in the pull-out HT and thermosol process.

Example 15 As in Example 14, the reaction of the compound (3) with methyl chloroformate gives 9.2 g (68.8% of theory) of the compound of the formula as yellow crystals which can be recrystallized from 1,2-dichlorobenzene (melting point 229-32 "C; fluorescence in DMF:" max,: 372 nm).

Example 16 To a solution of 22.7 g (0.08 mol) of 5-ethoxy-2- (4'-bromo-methylphenyl) -1f3ff4-oxadiazole 16.6 g of triethyl phosphite are added dropwise to 80 ml of toluene at 100 ° C. under nitrogen to that the resulting bromoethane distills off immediately.

The mixture is stirred for 4 hours at about 1100C and then removed the toluene and excess triethyl phosphite in vacuo.

100 ml of dimethylformamide and 19 g (0.08 mol) of 2- (4'-formyl-phenyl) -5-methyl-benzoxazole are added to the residue added up. At 50 ° C, 100 ml (0.1 mol) of a 1 molar sodium methylate solution are added to the mixture added dropwise and stirred at 600C for 4 hours. The mixture is brought to room temperature cooled, neutralized with 6.6 g - (0.11 mol) glacial acetic acid and treated with 100 ml of ethanol.

Filtering off, washing with ethanol and drying in vacuo at 50 ° C. yields 20.1 g (59.5% of theory). Very clean raw product of the formula which is recrystallized from xylene (melting point: 215 "C, max: 366 nm). The compound provides excellent whitening effects from PES with very good fastness properties.

2- (4'-Bromo-methylphenyl) -5-ethoxy-1,3,4-oxadiazole is in itself in a known manner from the corresponding tolyl compound by bromination with N-bromosuccinimide made in carbon tetrachloride.

In a manner analogous to that described in Examples 14-16, the following compounds are also prepared: Sr AQ fluorescence in D: o: 7 ¾) -OCH3 blue , ~ .. 3 CH3s "> Sz ' 18 Or C »2 5 neutral blue J CH3 Ch3 CH3 19 CH3 <QH2CH2OCH3 neL'tr. blue 20 <~ 0C4H9 blue No. AQ fluorescence in DMF 21 -OC: 2C: -: 2Cl .. 22 9 N- -O-H2 N rotst bl - td respectively N - N 23 CH3 to O to -OCH3 blank C H39 ' N C »-OCH3 intensive blue 0 CH3OOC N CH3 25 3 ob XO -OCH violet blue I O 3 'OC82CH20C2H, blue 26th 27 Og N (CH3) green bla ' Cl N 23 C1 -NH2 N -> 4H2 green. building 0 CI / -7 39 is. gr Example 30 To a suspension of 13.7 g (0.05 mol) of 2- (4-formylphenyl) naphth [1,2-d] -1,2,3-triazole and 15.6 g (0.05 mol ) 3- (4-DiethOxyphosphonomethylphenyl) -1,2,4-oxadiazol-5-one in 150 ml of anhydrous dimethylformamide are added dropwise at 50 ° C. within 30 min. 20 g (0.11 mol) of 30% sodium methylate solution . The mixture is stirred for 3 hours at 50-60 ° C and then with 20 g of conc. Acetic acid added. After cooling, it is filtered off and washed successively with 50 ml each of 5% hydrochloric acid, water and methanol. Drying in vac. at 50 ° C. yields 13.6 g (63% of theory) of pale yellow crystal powder of the compound of the formula which can be recrystallized from dimethylformamide.

Melting point:> 300 ° C, IR (KBr): 3430 cm-1, 1760 cm-1, 1599 cm-1, UV absorption (DMF): #max = 374 nm.

The diethoxy-phosphono-methyl compound of the formula used is prepared as follows: 28 g (0.4 mol) of hydroxylamine hydrochloride and 20 g (0.2 mol) of sodium carbonate are dissolved in 300 ml of cest. Dissolved water.

27.8 g (0.11 mol) of 4- (diethoxyphosphonomethyl) are added dropwise to the solution benzonitrile and stir for 2 hours at 80.degree. After cooling to room temperature, 3 x extracted with 100 ml of chloroform and the combined chloroform phases over dried anhydrous sodium sulfate. The solvent is in the Vac. removed and the crude oil obtained was dissolved in 100 ml of anhydrous xylene.

17.8 g (0.11 mol) of ethyl pyrocarbonate are added and the rate is increased the internal temperature slowly, with initially ethanol and later xylene distilling off (approx 2-3 hours).

When the reaction is complete, the solvent is halfway through Removed distillation and cooled. Filter off and dry in vacuo at 500C yields 26.2 g (76.3% of theory) of colorless crystals with a melting point of 196-201 "C Ethanol can be recrystallized C13H17N2O5 P (312i3) C% H% N% Ber: 50.0 5.49 8.97 Found: 49.9 5.4 8.6 Example 31 11.2 g (0.05 mol) of 2- (4-formyl-phenyl) -benzoxazole and 15.6 g (0.05 mol) of 3- (4-diethoxyphosphonomethylphenyl) -1,2,4-oxad-iazolin-5-one are suspended in 100 ml of anhydrous dimethylformamide and in the same way as described in Example 30, reacted and isolated.

15.2 g (79.7% of theory) of pale crystals of the compound of the formula are obtained which can be recrystallized from dimethylformamide.

M.p .:> 3000C; IR (KBr): 3425 cm-1, 1760 cm-1, 1605 cm-1, UV absorption (in DMF) man = 362 nm.

max Example 32 Analogously to Example 30, 14.1 g (0.05 mol) of 2- (4-formyl-phenyl) -5-carbmethoxy-benzoxazole and 15.6 g (0.05 mol) of 3- (4- Diethoxy-phosphonomethyl-phenyl) -1,2,4-oxadiazolin-5-one 16.5 g (75.1% of theory) of pale yellow crystals of the compound of the formula which can be recrystallized from dimethylacetamide.

M.p.> 3000C; IR (KBr) 3420 cm -1, 1765 cm -1, 1735 cm -1, 1600 cm UV absorption (in DMF) #max = 364 nm.

Example 33 8.63 g (0.02 mol) of the compound (30) are in 100 ml Suspended anhydrous dimethylformamide and 4 g (0.022 mol) of 30% sodium methylate solution added. After stirring at 50 ° C. for 1 hour, 3.74 g (0.022 mol) of 2-iodopropane are added dropwise and the reaction mixture is stirred at 80 ° C. for 4 hours. At 500C it is filtered off, the The filtrate was concentrated to dryness and concentrated with 50 ml of water and 10 g.

Acetic acid treated. Filtering off and drying in vacuo at 50 ° C. yields 6.1 g (64.4% of theory) of yellow crystal powder of the compound of the formula which can be recrystallized from dimethylacetamide -1 (UV absorption (DMF): l max = 372 nm; IR (KBr): 3430 cm 1775 cm 1, 1605 cm 1).

Example 34 For the suspension of 11.9 g (0.05 mol) 2- (4-formyl-phenyl) -5-methyl-benzoxazole and 15.6 g (0.05 mol) 3- (4-diethoxyphosphonomethyl-phenyl) 1,2,4-oxadiazolin-5-one in 100 ml of anhydrous dimethylformamide is added dropwise at 50 ° C. within 30 minutes. 20 g (0.11 mol) of 30% sodium methylate solution. The mixture is stirred at 50-60 ° C. for about 3 hours until the reaction is complete. 8.4 g (0.055 mol) of methyl bromoacetate are then added and the mixture is stirred at 90 ° C. for 3 hours. After cooling to room temperature, 20 g of conc. Acetic acid is added, the yellow precipitate is filtered off, washed with water and methanol and dried. in vac. at 50 "C. Yield 15.3 q (65.4% of theory) of the compound of the formula which can be recrystallized from methyl glycol.

(UV absorption (DMF): g max = 364 nm).

The following compounds are also prepared in a manner analogous to that described in Examples 30-34: No. A1 W fluorescence in DMF , ON 35 W \ »-CH2-COOC2H5 rotst. blue CH 0 36 <11H H red-violet- ° blue 37 - "- CH3 rotst. Blue CH3 38 CH3% -C4H9 blue CH3 39 <-CH2 <very rotst. - Blue 40> ~ -CH2-CH = CH2 neutral blue c. 41 W $ N / H little green. blue No. A1 W fluorescence in AW DMF in DMF CH 42 /; N / H blue 42 \ NH blue t1 ' 43 - "- H blue H v N y N / CH3 44 4 N wCH3 reddish tinged blue CH-C CHZ-COOC2H5 very blue 45 2 OOC H very blue NN 46 4t> N 46 H rotst. blue NN CCO> C2H5 blue N- N 48 CH3O¼ {0 # -C6H5 blue violet

Example 49 To a solution of 22.7 g (0.08 mol) of 5-ethoxy-3- (4-bromomethyl-phenyl) -1,2,4-oxadiazole in 80 ml of abs. Toluene is added dropwise at 1000C under nitrogen, 20 g of triethyl phosphite so that the bromoethane formed is immediately distilled off. The mixture is stirred for 5 hours at about 1000C and the toluene and excess triethylphosphite are removed in vacuo. 100 ml of dimethylformamide and 21.9 g (0.08 mol) of 2- (4-formylphenyl) naphth / 1,2-d7-1,2,3-triazole are added to the residue. At 50 ° C., 100 ml (0.1 mol) of a 1 molar sodium ethoxide solution are added dropwise to the mixture and the mixture is stirred for 4 hours at 50-60 ° C. The mixture is cooled to room temperature, with 6.6 g (0.11 mol) Glacial acetic acid is neutralized and filtered off, washing with ethanol and drying in vacuo at 50 ° C. gives 23.0 g (62.5% of theory) of yellow crystals of the compound of the formula which can be recrystallized from chlorobenzene (UV absorption (in DMF) Amax = 370 nm). 5-Ethoxy-3- (4-bromomethyl-phenyl) -1,2,4-oxadiazole is obtained from 3- (4-methyl-phenyl) 1,2,4-oxadiazole (cf. F. Eloy, A. Deryckere , A. van Overstraeten Bull. Soc. Chim. Belges 78 (1969) 47-54) in a known manner by bromination with N-bromosuccinimide in carbon tetrachloride.

Example 50 Analogously to Example 49, 11.2 g (0.05 mol) of 2- (4-formyl-phenyl) -benzoxazole and 14.2 g (0.05 mol) of 5-ethoxy-3- (4-bromomethylphenyl) are obtained ) -1,2,4-oxadiazole, 15.5 g (75.6% of theory) of the compound of the formula which is recrystallized from chlorobenzene (UV absorption (in DMF) max 360 nm).

The following connections are also established in an analogous manner: No. A2 Q1 fluorescence in No. A2 Q1 Hallway in DMF 51 </ - -OCH3 strong blue No AQ fluorescence in DMF CH30, N 52 C 3 ° CN / -OCH3 somewhat green. blue 53 WN {X: H2COCH3 strongly blue violet 54 a -OC 4H9 -n blue violet 55 I -OCH2 rotst. blue 55; C CH 56 v nu -OC3H7 -i blue CH3 5 7 S / - -NHe green. blue

Example 58 14.5 g (0.03 mol) of compound 49 are dissolved in 100 ml of dimethylformamide Heated under reflux for 3 hours. After cooling to room temperature, 50 ml of methanol added and the precipitated product filtered off, washed with methanol and dried at 500C in vacuo.

11 g (75.9% of theory) of the compound of the formula are obtained which is recrystallized from dimethylacetamide (UV absorption (in DMF): imax = 373 nm).

Claims (9)

Claims 1. Compounds of the formula where A is a quasi-aromatic heterocyclic radical, B is a radical of the formulas n for 0, 1, 2 or 3, preferably 0-2, R1 for hydrogen, CN, R, -COR, SO2R, COOR, CONHR or CON (R ') 2 R2 for hydrogen, halogen, -OR, -NHR, -N (R ') 2 or NHCOR, R' for alkyl and R for R ', alkenyl, aralkyl, cycloalkyl or aryl, where A, B, R' and R carry further non-chromophoric substituents customary in the chemistry of optical brighteners can. 2. Compounds according to claim 1, characterized in that A represents a 1,2,4-oxadiazole, 1,3,4-oxadiazole, 1,2,3-triazole, one optionally by 1-2 C1-C4 -Alkyl, C1-C4-alkoxy, 1-2 chlorine, benzyl, phenyl, cyclohexyl, C1-C4-alkylsulfonyl or C1-C4 -alkoxycarbonyl-substituted benzoxazole, benzo (b) -furan, benzo-s-triazole-, Naphtho-s-triazole, 5-phenyl-1,3,4-oxadiazole, 5-phenyl-1,2,4-oxadiazole or 3-phenyl-1,2,4-oxadiazole radical and B for one Remainder of the formula (or mixtures of the two) where R1 is hydrogen, allyl, C1-C4 -alkoxycarbonyl, an alkyl radical optionally substituted by hydroxy, acetoxy, C1-C4-alkoxy, phenoxy, chlorine, cyanol sulfo or CF3, or an alkyl radical optionally substituted by C1-C4 -Alkyl, C1-C4-alkoxy, C1-C4-alkoxycarbonyl, cyano or chlorine-substituted benzyl or benzoyl radical. 3. Compounds according to claims 1 and 2, characterized in that A has the meaning given in claim 2, B for a remainder of the formulas where R2 is hydrogen, chlorine, amino, C1-C4-alkylamino, phenylamino or a radical of the formula (OCH2CH2) where W is hydrogen, C1-C6-alkyl, benzyl, cyclohexyl or phenyl optionally substituted by chlorine or cyano, and m is a whole Number from 0 to 7 mean. 4. Compounds according to claim 1 and 2, characterized in that A has the meaning given in claim 2, B for a radical of the formula in which R1 is hydrogen, C1-C4-alkyl or phenyl which is optionally substituted by hydroxy, C1-C4-alkoxy, chlorine, cyano, C1-C4-alkoxycarbonyl or phenyl. 5. Compounds according to claim 1, characterized in that A represents the remainder of the formula and B for the rest of the formulas where n = 1 and where V1 is hydrogen, C1-C4-alkyl, cyclohexyl, C1-C4-alkoxy, chlorine, benzyl, phenyl, C1-C4-alkoxycarbonyl, C1-C4-alkylsulfonyl, V2 is hydrogen, C1-C4-alkyl , Chlorine or C1-C4-alkoxy, V3 denotes hydrogen, C1-C4-alkyl or chlorine and V4 denotes C1-C6-alkyl, benzyl, cyclohexyl or phenyl optionally substituted by C1-C4-alkoxy, hydroxy, chlorine or cyano. 6. Compounds according to claims 1 to 5, characterized in that A for optionally - as indicated in the preceding claims - substituted Benzoxazolyl-2 or benzo-s-triazolyl-2. 7. A compound according to claim 1 of the formula where V1 is hydrogen, methyl or chlorine and V4 is methyl, ethyl, n-propyl, isopropyl or n-butyl. 8. A compound according to claim 1 of the formula 9. Use of the compounds according to Claim 1 as optical brighteners for laser dyes.