GB2103231A - Dyestuffs comprising two 5- membered heterocyclic nuclei fused to a central cyclohexa-1,4-diene nucleus - Google Patents

Abstract

This specification describes dyestuffs of the formula: <IMAGE> wherein Z<1> and Z<2> are oxygen, sulphur or <IMAGE> in which Y<1> is an optionally substituted hydrocarbon radical or an acyl radical; R<3> and R<4> each independently represent a naphthyl or a phenyl radical at least one of which is substituted by an acetoxy group, and which may be further substituted by at least one of the following:- nitro, halogen, optionally substituted lower alkyl, optionally substituted lower alkoxy, phenyl, hydroxy, lower alkoxyphenyl, phenoxy, cyano, carboxylic acid, carboxylic acid ester, optionally substituted carbamoyl, sulphonic acid, sulphonyl chloride, sulphonic acid ester, optionally substituted sulphamoyl, mercapto, lower alkylthio, phenylthio, primary, secondary, tertiary or quaternary amino, acylamino, phosphonic acid, phosphonic acid ester, lower alkylsulphonyl, phenylsulphonyl, aldehyde, optionally substituted phenylazo and acyloxy; and X<3> and X<4> each independently represent hydrogen, chlorine, bromine, cyano, lower alkyl, lower alkoxy, optionally substituted aryl, optionally substituted carbamoyl, optionally substituted sulphamoyl, carboxylic acid or carboxylic acid ester, provided that when R<3> and R<4> are both acetoxyphenyl radicals free from other substituents then Z<1> and Z<2> are not both oxygen. The dyestuffs are useful for the colouration of a wide range of materials.

Description

SPECIFICATION Dyestuffs comprising two 5-membered heterocyclic nuclei fused to a central cyclohexa-1 ,4- diene nucleus This invention relates to dyestuffs comprising two 5-membered heterocyclic nuclei fused to a central cyclohexadiene nucleus.

United States Patent Specification No. 411 5404 discloses dyestuffs of the general formula:

wherein each Z is oxygen or -NY in which Y is an optionally substituted hydrocarbon radical or an acyl radical; R' and R2 each independently represent a naphthyl radical, an unsubstituted phenyl radical or a phenyl radical substituted by at least one of the following: nitro, halogen, lower alkyl, lower alkoxy, phenyl, lower alkoxyphenyl, phenoxy, cyano, carboxylic acid, carboxylic acid ester, optionally substituted carbamoyl, sulphonic acid, sulphonyl chloride, sulphonic acid ester, optionally substituted sulphamoyl, mercapto, lower alkylthio, phenyl thio, primary, secondary, tertiary or quaternary amino, acyl amino, phosphonic acid, phosphonic acid ester, lower alkylsulphonyl, phenylsulphonyl, aldehyde, azo, and acyloxy groups of the formula 0.- CO.T in which T is an alkyl group containing at least two carbon atoms, a substituted phenyl group, a lower alkoxy group or a phenoxy group; and X' and X2 each independently represent a hydrogen atom, chlorine, bromine, cyano, lower alkyl, lower alkoxy, optionally substituted carbamoyl, carboxylic acid or carboxylic acid ester group.

According to the present invention there are provided dyestuffs of the general formula (I):

wherein Z' and Z2 are oxygen, sulphur or -N-Y1 in which V1 is an optionally substituted hydrocarbon radical or an acyl radical; R3 and R4 each independently represent a naphthyl or a phenyl radical at least one of which is substituted by an acetoxy group, and which may be further substituted by at least one of the following::- nitro, halogen, optionally substituted lower alkyl, optionally substituted lower alkoxy, phenyl, hydroxy, lower alkoxyphenyl, phenoxy, cyano, carboxylic acid, carboxylic acid ester, optionally substituted carbamoyl, sulphonic acid, sulphonyl chloride, sulphonic acid ester, optionally substituted sulphamoyl, mercapto, lower alkylthio, phenylthio, primary, secondary, tertiary or quaternary amino, acylamino, phosphonic acid, phosphonic acid ester, lower alkylsulphonyl, phenylsulphonyl, aldehyde, optionally substituted phenylazo and acyloxy; and X3 and X4 each independently represent hydrogen, chlorine, bromine, cyano, lower alkyl, lower alkoxy, optionally substituted aryl, optionally substituted carbamoyl, optionally substituted sulphamoyl, carboxylic acid or carboxylic acid ester, provided that when R3 and R4 are both acetoxyphenyl radicals free from other substituents then Z: and Z2 are not both oxygen.

Examples of the optionally substituted hydrocarbon radicals represented by Y' are alkyl and preferably lower alkyl such as methyl, ethyl, n-propyl and isopropyl, substituted alkyl and preferably substituted lower alkyl such as p-hydroxyethyl, p-methoxyethyl and 5-ethoxyethyl, phenyl and substituted phenyl such as tolyl, chlorophenyl and nitrophenyl, and lower alkoxyphenyl such as methoxyphenyl, dimethoxyphenyl and ethoxyphenyl.

Examples of the acyl radicals represented by Y' are acetyl, propionyl, butyryl, isobutyryl, unsubstituted benzoyl and benzoyl substituted by halogen, nitro, hydroxy, lower alkyl such as methyl, or lower alkoxy such as methoxy or ethoxy.

Examples of optionally substituted aryl groups represented by X3 and X4 are unsubstituted phenyl and phenyl substituted in ortho, meta orpara positions by halogen, lower alkyl such as methyl, nitro, lower alkoxy such as methoxy or ethoxy, phenyl or carboxylic acid ester. Two or more such substituents, which may be the same or different, may be present.

The lower alkyl groups represented by X3 and X4 may be, for example, methyl groups, and the lower alkoxy groups represented by X3 and X4 may be, for example, methoxy and ethoxy groups.

Examples of lower alkylthio and lower alkyl sulphonyl groups which may be present as substituents on the phenyl radicals represented by R3 and R4 are methylthio, ethylthio, methylsulphonyl and ethylsulphonyl.

Examples of acylamino groups which may be present as substituents on the phenyl radicals represented by R3 and R4 are acetylamino, propionylamino, benzoylamino, methanesulphonylamino, benzenesulphonylamino and toluenesulphonylamino.

The acyloxy groups which may be present as substituents on the phenyl radicals represented by R3 and R4 are preferably of the formula -O.CO.T1 in which 11 is lower alkyl, lower alkoxy, optionally substituted phenyl, or phenoxy.

Examples of lower alkyl, lower alkoxy and substituted phenyl groups represented by T1 are methyl, ethyl, methoxy, ethoxy, tolyl, chlorophenyl and lower alkoxyphenyl as defined for V1.

The optionally substituted carbamoyl and suiphamoyl groups which may be present as substituents on the phenyl radicals represented by R3 and R4, and which are represented by X3 and X4, are preferably of the formula:

respectively wherein L' and L2 are each independently hydrogen, lower alkyl or phenyl.

The carboxylic acid ester groups which may be present as substituents on the phenyl radicals represented by R3 and R4, and which are represented by X3 and X4 are preferably of the formula: COOL3 wherein L3 is an optionally substituted alkyl, in particular lower alkyl or monocyclic aryl, in particular phenyl, radical.

The sulphonic acid ester groups which may be present as substituents on the phenyl radicals represented by R3 and R4 are preferably of the formula -S020L3 in which L3 has the above-defined meaning.

Throughout this specification the terms "lower alkyl" and "lower alkoxy" are used to denote alkyl and alkoxy groups respectively containing from 1 to 4 carbon atoms.

The dyestuffs of formula (I) may be prepared by acetylation of an intermediate of formula (ill):

wherein X3, X4, Z1 and Z2 have the previously defined meanings and R5 and R6 each independently represent a naphthyl or a phenyl radical at least one of which is substituted by a hydroxyl group and which may be further substituted by at least one of the substituents previously defined for R3 and R4.

The acetylation may be carried out by conventional means, for example, by treating the intermediate of formula (II) with an acetylating agent such as acetyl chloride or acetic anhydride in the presence of an acid-binding agent, for example, a tertiary amine such as triethylamine or pyridine, preferably at a moderately elevated temperature and preferably in the presence of an inert solvent such as dioxan. The resulting dyestuff of formula (I) may usually be isolated by pouring the reaction mixture into water when the inert solvent is water-miscible, or, when the inert solvent is not water-miscible, by adding to the reaction mixture an organic liquid which is miscible with the inert solvent but which is not a solvent for the dyestuff. The precipitated dyestuff may then be collected.

Symmetrical intermediates of formula (II) may be prepared by reaction of 1 mol proportion of a compound of formula (III):

wherein X3, X4, Z1 and Z2 have the previously defined meanings, with at least 2 mol proportions of a compound of formula (IV):

wherein B is hydrogen, lower alkyl or aryl, A is hydroxyl, O-acyl or halogen, and R5 has the previously defined meaning. The reaction may be carried out in the absence of solvent, i.e. as a melt, or preferably in the presence of an inert high-boiling solvent such as di- or trichlorobenzene.

Specific examples of compounds of formula (III) which may be used in the above process are hydroquinone, 4-mercaptophenol, 4-acetamidophenol, 4-N-methylaminophenyl and 4-Nisopropylaminophenol.

Specific examples of compounds of formula (IV) which may be used are 4-hydroxymandelic acid, 3,5-dimethyl-4-hydroxymandelic acid, 4-hydroxy-3-methylmandelic acid and 3-chloro-4hydroxymandelic acid.

A reaction temperature of 190-1 950C is generally satisfactory, although temperatures higher or lower than this may be used in particular circumstances.

The product initially obtained from the above reaction is the dihydro intermediate of formula (V):

which in some cases may be sufficiently stable to be isolated, although it may oxidise spontaneously in the presence of air to give the intermediate of formula (II) directly. The oxidation step may also be carried out, for example, by heating the compound of formula (V) in nitrobenzene or by treating it with another oxidising agent such as hydrogen peroxide in acetic acid.

Intermediates for dyestuffs of formula (I) in which R3 and R4 may be either the same or different may be prepared by the stepwise reaction scheme given below

I 0 1 0 R6 o%idise ; > 0 0 (V) (11) wherein A, B, R5, R6, X3, X4, Z1 and Z2 have the previously defined meanings.

In a variation of the above scheme intermediates of formula (li) in which R5 and Re are different may be prepared in admixture with intermediates of formula (I) in which R5 and R5 are the same by reacting the compound of formula (IV) with a mixture of the compound of formula (1V) and the compound of formula (VII). In this generalised example it is assumed that X3=X4 and that Z1=Z2. If this is not so then further isomers are possible but components where R5 and R5 are different will be present.

When Z1 and Z2 are both oxygen, intermediates of formula (II) in which R5 and Rs are different may also be obtained by reaction of the quinone of formula (VIII):

with a compound of the formula (IX):

wherein B, R5, X3 and X4 have the previously defined meanings, Q is hydrogen, hydroxyl or O-acyl and X5 and X6 are hydrogen, chlorine or bromine, provided that when 0 is hydrogen, at least X3 and X4, or X5 and X6, must be chlorine or bromine, to give a compound of the formula (X):

which is then further reacted with a compound of formula (Xl):

wherein B, Q and Re have the previously defined meanings, to give a compound of the formula (XII)::

which then cyclises with bond rearrangement to give an intermediate of formula (II) in which Z1 and Z2 are both oxygen.

Dyestuffs of formula (I) may also be synthesised directly using any of the routes indicated above by employing compounds of formulae (IV), (VII), (IX) or (Xl) in which at least one of the phenyl or naphthyl radicals represented by R5 and R6 contains an acetoxy group.

Having prepared dyestuffs by the methods of synthesis described above, other substituents can be introduced by conventional methods, or substituents already present can be converted into other substituents in known manner. The following are illustrative of such reactions:- (a) sulphuric acid groups can be introduced by sulphonation methods, and sulphonyl chloride groups by reaction with chlorosulphonic acid, (b) nitro groups can be introduced by nitration methods, (c) hydroxy groups can be converted into acyloxy groups by treatment with acylating agents, (d) nitro groups can be reduced to amino groups, (e) amino groups can be converted into acylamino groups by treatment with acylating agents, (f) tertiary amino groups can be converted into quaternary amino groups.

If desired, the structure of the dyestuff of the present invention can also be incorporated into other dyestuff systems. Thus, for example, dyestuffs containing both the said structure and an azo system can be prepared by coupling a diazotised amino on to a dyestuff of the present invention which contains a phenolic hydroxy group. Alternatively a dyestuff of the present invention which contains a diazotisable amino group can be diazotised and coupled on to a coupling component. Also a dyestuff of the present invention which additionally contains an azo group can be obtained by synthesis of the dyestuff directly from an intermediate which already contains an azo group.As a further example, dyestuffs containing both the structure of the present dyestuffs and a nitro dyestuff system can be obtained by, for example, condensing a dyestuff of the present invention containing an aminophenyl residue with a halogenonitrobenzene.

The dyestuffs of the invention are valuable for colouring natural and synthetic textile materials.

Thus the dyestuffs of the invention which are free from water-solubilising groups (i.e. suiphonic acid, carboxylic acid or quaternary ammonium groups) are valuable for colouring synthetic textile materials, for example cellulose acetate and cellulose triacetate textile materials, polyamide textile materials such as polyhexamethyleneadipamide textile materials, polyacrylonitrile textile materials, and preferably aromatic polyester textile materials such as polyethylene terephthalate textile materials. Such textile materials can be in the form of threads, yarn, or woven or knitted fabric. If desired, the said synthetic textile materials may be made from blends of natural and synthetic fibres. Examples of such materials are polyester/cellulose and polyester/wool textile materials.

Such textile materials can conveniently be coloured with the water-insoluble dyestuffs, as hereinbefore defined, by immersing the textile material in a dyebath comprising an aqueous dispersion of one or more of the said dyestuffs, which dyebath preferably contains a non-ionic, cationic and/or anionic surface-active agent, and thereafter heating the dyebath for a period at a suitable temperature.

In the case of secondary cellulose acetate textile materials it is preferred to carry out the dyeing process at a temperature between 600 and 850C; in the case of cellulose triacetate or polyamide textile materials it is preferred to carry out the dyeing process at 95 to 100 C; in the case of aromatic polyester textile materials the dyeing process can either be carried out at a temperature between 900 and 100 C, preferably in the presence of a carrier such as diphenyl or o-hydroxydiphenyl, or at a temperature above 100 C, preferably at a temperature between 1200 and 1400 C, under superatmospheric pressure.

Alternatively, the aqueous dispersion of the said dyestuff can be applied to the textile material by a padding or printing process, followed by heating at temperatures up to 2300C depending on the textile material, or by steaming of the textile material. In such processes it is preferred to incorporate a thickening agent, such as gum tragacanth, gum arabic or sodium alginate, into the aqueous dispersion of the said azo dyestuff.

At the conclusion of the colouring process it is preferred to give the coloured textile material a rinse in water or a brief soaping treatment before finally drying the coloured textile material. In the case of aromatic polyester textile materials it is also preferred to subject the coloured textile material to a treatment in an aqueous solution of an alkali, such as sodium carbonate or sodium hydroxide, before the soaping treatment in order to remove loosely attached dyestuff from the surface of the textile material.

The water-insoluble dyestuffs have excellent affinity and building-up properties on aromatic polyester textile materials, so enabling deep shades to be obtained. The resulting colorations have good to excellent fastness to light, to wet treatments, to perspiration, and in particular to dry heat treatments such as those carried out at high temperatures during pleating operations.

If desired, the water-insoluble dyestuffs of the invention can be applied to synthetic textile materials in conjunction with other disperse dyes, such as are described in, for example, British Specifications Nos. 806271, 835819, 840903, 847175, 852396, 852493, 859899, 865328, 872204, 894012,908656, 909843, 910306, 913856, 919424, 944513, 944722, 953887, 959816,960235,961412, 976218,993162 and 998858.

Those dyestuffs of the invention which are soluble in water by virtue of the presence of quaternary ammonium groups can be used as Basic DyestufFs for the dyeing of polyacrylonitrile textile materials or of polyamide and polyester textile materials which contain acidic groups which confer affinity on such textile materials for Basic Dyestuffs. The said dyestuffs can be applied in conventional manner to these textile materials from acid, neutral or slightly alkaline dyebaths, the pH of which is preferably maintained in the range of 3 to 8, at temperatures between 400C and 1200 C, preferably between 800 and 1200C, or by printing techniques using thickened print pastes containing the said dyestuffs.

Those dyestuffs of the invention which are soluble in water by virtue of the presence of acidic water-solubilising groups can be used for colouring natural or synthetic polyamide textile materials such as wool, silk or polyhexamethylene adipamide textile materials. Such dyestuffs can be applied in conventional manner to the said textile materials from aqueous dyebaths, the pH of which is preferably maintained in the range of 4 to 8.

Those dyestuffs of the invention which contain acidic water-solubilising groups can be used for colouring cellulose textile materials, the dyestuffs being applied by conventional methods to such textile materials.

Dyestuffs of the invention can also be applied to textile materials by transfer printing processes, including such processes carried out at reduced pressures or under moist or humid conditions.

Dyestuffs of the invention can also be used in mass colouration processes.

Insoluble dyestuffs of the present invention may also be used as pigments for the colouration of inks and paints, such dyestuffs being incorporated in known manner into conventional ink or paint formulations.

The invention is illustrated by the following Examples in which parts and percentages are by weight.

Example 1 A mixture of 3.5 parts of 3-phenyl-7-(4-hydroxyphenyl)-2,6-dioxo-2,6-dihydrobenzo[1 :2-b, 4:5- bl]difuran,4.0 parts of triethylamine, 1.56 parts of acetyl chloride and 50.0 parts of dioxan is stirred at 600C for 2 hour. The solution is cooled to ambient temperature, poured into 500 parts of water and the precipitated solid is filtered off, washed with water and dried.

The product dissolves in chloroform to give a reddish-yellow solution having Amax 469 nm.

When applied to aromatic polyester textile materials from aqueous dispersions the product gives strong reddish-yellow shades with good fastness to light, heat and wet treatments.

The 3-phenyl-7-(4-hydroxyphenyl)-2,6-dioxo-2,6-dihydrobenzo[1 :2-b, 4:5-b']difuran used in this Example was prepared as follows:- A mixture of 9.04 parts of 5-hydroxy-2-oxo-3-phenyl-2,3-dihydrobenzofuran (itself prepared by reaction at room temperature between approximately equimolar quantities of hydroquinone and mandelic acid in acetic acid/sulphuric acid 95/5) and 6.72 parts of 4-hydroxymandelic acid is stirred for 1.5 hours at 1 950C, 8 parts of nitrobenzene are then added and heating is continued for a further 30 minutes. The mixture is cooled to 250 C, 100 parts of methanol are added and the mixture is stirred for 2 hours at 250C. The precipitated solid is filtered off, washed with methanol and dried.Crystallisation from cel losolve gives 3-phenyl-7-(4-hydroxyphenyl)-2,6-dioxo-2,6-dihydrobenzo[1 :2-b, 4:5-b']difuran.

[Found: C 74.2; H 3.3. C22H,205 required C 74.16; H 3.37%].

Example 2 A mixture of 1.4 parts of 3-(4-n-propoxyphenyl)-7-(4-hydroxyphenyl)-2 6-dioxo-2,6- dihydrobenzo[1 :2-b, 4:5-b']difuran, 2.0 parts of triethylamine, 0.78 parts of acetyl chloride and 30.0 parts of dioxan is stirred at 700C for - hour. The solution is cooled to ambient temperature, poured into 250 parts of water and the precipitated solid is filtered off, washed with water and dried.

The product dissolves in chloroform to give a bluish-red solution having Amax 510 nm. When applied to aromatic polyester textile materials from aqueous dispersions the product gives strong bluish-red shades with good fastness to light, heat and wet treatments.

The 3-(4-n-propoxyphenyl)-7-(4-hydroxyphenyl)-2,6-dioxo-2,6-dihydrobenzo[ :2-b, 4:5- b']difuran used in this Example was prepared from 5-hydroxy-2-oxo-3-(4-n-propoxyphenyl)-2,3dihydrobenzofuran (itself prepared by reaction at room temperature between approximately equimolar quantities of hydroquinone and 4-n-propoxymandelic acid in acetic acid/sulphuric acid 95/5) and 4hydroxymandelic acid by the method described in the final paragraph of Example 1.

Example 3 A mixture of 1.1 parts of 3-(4-n-propoxyphenyl)-7-(3,5-dimethyl-4-hydroxyphenyl)-2 6-dioxo- 2,6-dihydrobenzo[1 :2-b, 4:51-b]difuran, 2 parts of triethylamine, 2.0 parts of acetyl chloride and 25.0 parts of dioxan is stirred at 400C for 5 minutes. The solution is cooled to ambient temperature, poured into 250 parts of water and the precipitated solid is filtered off, washed with water and dried.

The product dissolves in chloroform to give a bluish-red solution having Amax 511 nm. When applied to aromatic polyester textile materials from aqueous dispersions the product gives strong bluish-red shades with good fastness to light, heat and wet treatments.

The 3-(4-n-propoxyphenyl)-7-(3,5-dimethyl4-hydroxyphenyl)-2,6-dioXo-2,6-dEhydrobenzo[1 :2-b, 4:5-b']difuran used in this Example was prepared from 5-hydroxy-2-oxo-3-(4-n-propoxyphenyl)-2,3dihydrobenzofuran (see Example 2) and 3,5-dimethyl-4-hydroxymandelic acid by the method described in the final paragraph of Example 1.

Example 4 A mixture of 3.87 parts of 3-(4-methoxyphenyl)-7-(4-hydroxyphenyl)-2,6-dioxo-2,6- dihydrobenzo[1 :2-b, 4:5-b1]difuran, 5.0 parts of triethylamine, 5.0 parts of acetyl chloride and 50.0 parts of dioxan is stirred at 400C for T hour. The solution is cooled to ambient temperature, poured into 500 parts of water and the precipitated solid is filtered off, washed with water and dried.

The product dissolves in chloroform to give a bluish-red solution having Amax 507 nm. When applied to aromatic polyester textile materials from aqueous dispersions the product gives strong bluish-red shades with good fastness to light, heat and wet treatments.

The 3-(4-methoxyphenyl)-7-(4-hydroxyphenyl)-2,6-dioxo-2,6-dihydrobenzo[ :2-b,4 :5-b']difu ran used in this Example was prepared from 5-hydroxy-2-oxo-3-(4-methoxyphenyl)-2 ,3-dihydrobenzof uran (itself prepared by reaction at room temperature between approximately equimolar quantities of hydroquinone and 4-methoxymandelic acid in acetic acid/sulphuric acid 95/5) and 4-hydroxymandelic acid by the method described in the final paragraph of Example 1.

Example 5 A mixture of 3.21 parts of 3-(4-n-propoxyphenyl)-7-(3-methyl-4-hydroxyphenyl)-2,6-dioXo-2,6- dihydrobenzo[1 :2-b, 4:5-b']difuran, 3 parts of triethylamine, 0.6 part of acetyl chloride and 50 parts of dioxan is stirred at 400C for 2 hour. The mixture is cooled to ambient temperature, poured into 300 parts of water and the precipitated solid filtered off, washed with water and dried. The product dissolves in chloroform to give a red solution having Amax 508 nm. When applied to aromatic polyester textile materials from aqueous dispersions it gives strong bluish-red shades with good fastness to light, heat and wet treatments.

The 3-(4-n-propoxyphenyl)-7-(3-methyl-4-hydroxyphenyl)-2,6-dioXo-2,6-dihydrobenzo[1 1:2-b, 4:5-b']difuran used in this Example was prepared from 5-hydroxy-2-oxo-3-(4-n-propoxyphenyl)-2,3dihydrobenzofuran and 3-methyl-4-hydroxy-mandelic acid by the method described in the final paragraph of Example 1.

Example 6 A mixture of 4.05 parts of 3-(4-methylphenyl)-7-(3-chloro-4-hydroxyphenyl)-2,6-dioxo-2,6- dihydrobenzo[l:2-b, 4:5-b']difuran 4 parts of triethylamine, 0.79 parts of acetyl chloride and 50 parts of dioxan is stirred at 500C for + hour. The mixture is then poured into 300 parts of water and the precipitated solid filtered off, washed with water, methanol and dried. The product dissolves in chloroform to give an orange solution having Amax 479 nm. When applied to aromatic polyester textile materials it gives reddish-orange shades with good fastness to light, heat and wet treatments.

The 3-(4-methylphenyl)-7-(3-chloro-4-hydroxyphenyl)-2,6-dioxo-2,6-dihydrobenzo[ :2-b, 4:5- b']difuran used in this Example was prepared from 5-hydroxy-2-oxo-3-(4-methylphenyl)-2,3dihydrobenzofuran (itself prepared by reaction at room temperature between approximately equimolar quantities of hydroquinone and 4-methylmandelic acid in acetic acid/sulphuric acid 95/5) and 3chloro-4-hydroxymandelic acid by the method described in the final paragraph of Example 1.

Example 7 The procedure described in Example 6 was repeated except that the 4.05 parts of 3-(4 methylphenyl)-7-(3-chloro-4-hydroxyphenyl)-2 ,6-dioxo-2,6-dihydrobenzo[ :2-b, 4:5-b']difuran was replaced by 3.84 parts of 3-(4-methylphenyl)-7-(3-methyl-4-hydroxyphenyl)-2,6-dioxo-2,6- dihydrobenzo[l:2-b, 4:5-b']difuran. The product dissolves in chloroform to give a reddish-orange solution having Amax 484 nm and when applied to polyester materials gives reddish-orange shades with good fastness to light, heat and wet treatments.

The 3-(4-methylphenyl)-7-(3-methyl-4-hydroxyphenyl)-2,6-dioXo-2,6-dihydrobenzo[1 :2-b, 4:5- b']difuran used in this Example was prepared from 5-hydroxy-2-oxo-3-(4-methylphenyl)-2,3dihydrobenzofuran and 3-methyl-4-hydroxymandelic acid by the method described in the final paragraph of Example 1.

Example 8 The procedure described in Example 6 was repeated except that the 4.05 parts of 3-(4 methylphenyl)-7-(3-chloro-4-hydroxyphenyl)-2,6-dioxo-2,6-dihydrobenzo[ 1:2-b, 4 :5-b']difuran was replaced by 3.7 parts of 3-(4-methylphenyl)-7-(4-hydroxyphenyl)-2,6-dioXo-2,6-dihydrobenzo[1 :2-b, 4:5-b']difuran. The product dissolves in chloroform to give a reddish-orange solution having Amax 483 nm and when applied to polyester textile materials gives reddish-orange shades with good fastness to light, heat and wet treatments.

The 3-(4-methylphenyl)-7-(4-hydroxyphenyl)-2,6-dioXo-2,6-dihydrobenzo[1 :2-b,4:5-b']difuran used in this Example was prepared from 5-hydroxy-2-oxo-3-(4-methylphenyl)-2,3-dihydrobenzofuran and 4-hydroxymandelic acid by the method described in the final paragraph of Example 1.

Example 9 The procedure described in Example 6 was repeated except that in place of the 4.05 parts of 3 (4-methylphenyl)-7-(3-chloro-4-hydroxyphenyl)-2,6-dioXo-2,6-dihydrobenzo[1 1:2-b, 4:5-b']difuran there is used 3.92 parts of 3-phenyl-7-(3-chloro-4-hydroxyphenyl)-2,6-dioXo-2,6-dihydrobenzo[1 :2-b, 4:5-b']difuran. The product dissolves in chloroform to give a reddish-yellow solution having Amax 467 nm and when applied to polyester textile materials gives reddish-yellow shades with good fastness to light, heat and wet treatments.

The 3-phenyl-7-(3-chloro-4-hydroxyphenyl)-2,6-dioXo-2,6-dihydrobenzo[1 :2-b, 4:5-b']difuran used in this Example was prepared from 5-hydroxy-2-oxo-3-phenyl-2,3-dihydrobenzofuran and 3chloro-4-hydroxymandelic acid by the method described in the final paragraph of Example 1.

Claims (3)

Claims

1 A dyestuff of the formula

wherein Zr and Z2 are oxygen, sulphur or --N V1 in which Y' is an optionally substituted hydrocarbon radical or an acyl radical; R3 and R4 each independently represent a naphthyl or a phenyl radical at least one of which is substituted by an acetoxy group, and which may be further substituted by at least one of the following::-- nitro, halogen, optionally substituted lower alkyl, optionally substituted lower alkoxy, phenyl, hydroxy, lower alkoxyphenyl, phenoxy, cyano, carboxylic acid, carboxylic acid ester, optionally substituted carbamoyl, sulphonic acid, sulphonyl chloride, sulphuric acid ester, optionally substituted sulphamoyl, mercapto, lower alkylthio, phenylthio, primary, secondary, tertiary or quaternary amino, acylamino, phosphonic acid, phosphonic acid ester, lower alkylsulphonyl, phenylsulphonyl, aldehyde, optionally substituted phenylazo and acyloxy; and X3 and X4 each independently represent hydrogen, chlorine, bromine, cyano, lower alkyl, lower alkoxy, optionally substituted aryl, optionally substituted carbamoyl, optionally substituted sulphamoyl, carboxylic acid or carboxylic acid ester, provided that when R3 and R4 are both acetoxyphenyl radicals free from other substituents then Z1 and Z2 are not both oxygen.

2. A dyestuff as described in any one of the Examples.

3. A process for the preparation of a dyestuff according to Claim 1 which comprises the acetylation of a compound of the formula:

wherein X3, X4, Z1 and z2 have the previously defined meanings and R5 and Re each independently represent an optionally substituted naphthyl or phenyl radical at least one of which is substituted by a hvHmxvl nrnlln