DE2520148A1 - CHROMOGENIC QUINOXALINE COMPOUNDS - Google Patents

Description

2b2UH8

NCR CORPORATION Dayton, Ohio (V.St.A.)

Patent application Our reference: 2050 / GER

CHROMOGENIC QUINOXALINE COMPOUNDS

The invention relates to new chromogenic substances for Use in pressure-sensitive recording materials. In particular, the invention relates to new quinoxaline compounds which are essentially colorless solids and assume a colorless state in liquid solution, but on reaction contact with an acidic one The fabric turns into a dark colored state.

When used in marking systems a marking in the desired areas of a carrier web or a carrier sheet is effected in that a local reaction contact between the chromogenic substance and the acidic substance on or in the track or the leaf is brought about. The chromogenic substance can be applied by transfer to the carrier sheet or already be present in this. Through the Reaction contact, a dark color is achieved in the area to be marked.

Known pressure-sensitive, mark-forming systems contain color-forming components on and / or in one or more carrier sheets, the color-forming components by means of a separated by pressure breakable material

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are. If all components are on a single sheet, one speaks of an "autogenous reactive" Recording material. Are the color-forming components arranged on separate sheets, then one speaks of a "transmission system". Multiple carbon copy systems can be produced by laying sheets on top of one another that have a receiving surface and have a transfer surface on their underside.

The most commonly used carbonless material is a solution of basic chromogenic substances, for example phthalides, pyromelitiates and fluorans, enclosed in microscopic capsules, the are as a layer on one surface of a transfer sheet, while the adjacent side of the Receiving sheet with a Lewis acid, d. H. with a Electron acceptor, is sensitized. It is one large number of reagents of the Lewis acid type known to be used in conjunction with basic chromogens can be used. The most common are acidic clays such as attapulgite, Silton clay, zeolite, Bentonite, halloysite, kaolin and silicon dioxide. However, acidic reacting polymer substances are also used used, either alone or in combination with acidic clays. Examples of such polymeric substances are phenolic polymers, such as phenol-formaldehyde and phenol-acetylene polymers, maleic acid-rosins, in part or fully hydrolyzed styrene-maleic anhydride copolymers, carboxy-polymethylene and partially or fully hydrolyzed vinyl methyl ether maleic acid

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Anhydride copolymers and mixtures of these substances, a large one Number of such acidic polymers as well as solvents for them and for the chromogenic substances are described in German Patent 1,275,550.

The invention relates to new chromogenic compounds for use in those described above pressure-sensitive recording systems are suitable and which have a high color intensity and high lightfastness. Connections of a similar nature, namely chromogenic pyrazine compounds are described in German patent application P 22 59 409.8, to which the present application represents an additional application.

The invention thus relates to new chromogenic compounds which are characterized by the following structural formula:

^R 1

wherein X is one of the groups K, L, M, T, W or Z, and Y is one of the groups K, L, M or T, where

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and wherein R ,, R ₂ * R3, R * and Ry independently of one another hydrogen, chlorine or a nitro, alkyl, alkoxy or

Dial kylamino-radi kai mean; R, - and Rg hydrogen or

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denote a phenyl, benzyl or alkyl radical, provided that when R ₅ or R _{ß is} a phenyl or benzyl radical, the other group is hydrogen or a methyl radical; R _{8 is} hydrogen or a phenyl, alkyl or alkoxy radical; R _{g is} hydrogen or a phenyl or alkyl radical; R, _{Q is} hydrogen or an alkyl or alkoxy radical; R ,, is an alkoxy radical; and R, ~ is hydrogen or a methyl or ethyl radical; all alkyl and alkoxy groups having fewer than seven carbon atoms.

The quinoxaline compounds according to the invention consist of a number of different parts, of course the quinoxaline part is contained in all compounds. To the different possible combinations of the individual parts or units To illustrate, is on the attached drawing referenced, in which the various possible combinations are shown schematically by structural formulas are.

The drawing also illustrates the

step-by-step preparation of the quinoxaline compounds according to the invention. A quinoxaline dicarboxylic acid anhydride (I) is combined with a substrate reactant (K, L, M, T, W or Z) to give a quinoxaline keto acid (II). This is then combined with a substrate reactant (K, L, M or T) to produce the to obtain chromogenic quinoxaline compound (III).

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The dicarboxylic anhydride (I) has in the 6- and 7-positions of the quinoxaline the groups R, and R ~. R, and Rp are hydrogen, chlorine, a nitro, alkyl, Alkoxy or dialkylamino radicals, wherein the alkyl and Alkoxy groups methyl or methoxy, ethyl or ethoxy, propyl or propoxy (including isopropyl or isopropoxy), butyl or 3utoxy (including isobutyl or isobutoxy and tert-butyl or tert-butoxy), pentyl or pentoxy (including the corresponding isomers), Hexyl or hexoxy (including the corresponding Isomers) or other alkyl or alkoxy groups with fewer than seven carbon atoms.

The substrate reactant 4-aminophenyl (K)

has R ₃ in the 2-phenyl position, R ₄ in the 3-phenyl position, R ₅ and R _g on the amino group in the 4 position and R ₇ in the 6 position. R-, R. and R ₇ are hydrogen, chlorine, a nitro radical, an alkyl radical with fewer than seven carbon atoms, an alkoxy radical with fewer than seven carbon atoms or a dialkylamino radical. R ₅ and R _ß represent hydrogen, a phenyl or benzyl group or an alkyl group with fewer than seven carbon atoms, where when R ₅ or R _{ß is} a phenyl or benzyl group, the other radical is either hydrogen or a methyl radical sol I.

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The substrate reactant 3-pyrryl (L) has R _g in the 2- and 5-pyrrole positions and R _g in the 1-pyrrole position. The substrate reactant 3-indolyl (M) has Rg and R ₉ in the 2- or 1-indole position and R, Q in the 5-indole position. The substrate reactant 3Tßenzoindolyl (T) is _{substituted in R g} and R ₉ in the 2- and 1-benzoindole positions, respectively. The substrate reactant 2-pyrryl (W) has the substituent R _g in the 1-pyrrole position. The substrate reactant (2-alkoxy-5-ani1ine) phenyl (Z) is _{substituted with R ,, in the 2-phenyl position and with R ^ 2} ^{on the} aniline nitrogen.

In these reactants is Rg is hydrogen, an alkyl Radikai having less than seven carbon atoms, an alkoxy radical containing less than seven carbon atoms or a phenyl radical. R _g represents hydrogen, an alkyl Radikai having less than seven carbon atoms, or a phenyl -Radical. R, q is hydrogen, an alkyl or alkoxy radical with fewer than seven carbon atoms. R <, denotes an alkoxy radical with fewer than seven carbon atoms and R ₁₂ denotes hydrogen, a methyl or ethyl radical.

The compound (III) is the chromogenic compound according to the invention in which X is one of the substrate reactants (K), (L), (M), (T), (W) or (Z) and Y mean one of the substrate reactants (K), (L), (M) or (T).

., The invention is illustrated below with reference to Examples for the preparation of the compounds further explained. Other connections can be made in a similar fashion can be produced using appropriately substituted starting materials.

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example 1

Preparation of l, l-bis (3-methyl-4-diethylaminophenyl) -l- | [h]] - 3- L ^h D -furo Q, 4-b-quinoxalin-3-one.

First, N, N-diethyl-m-toluidine (unit K, where R ₃ = CH ₃ , R ₄ = H, R ₅ = R ₆ = C ₂ H ₅ and R ₇ = H) with 2,3-quinoxalic anhydride ( I, where R ₁ = R 2 = H) combined to give 2- (2-methyl-4-diethylaminobenzoyl) -3-quinoxalic acid. 0.1 mol of toluidine and 0.1 mol of anhydrous aluminum chloride are added to 50 ml of ice-cold methylene chloride. To this system, 0.02 mol of quinoxalic anhydride is added and the system is stirred overnight to carry out the reaction. The system is steam distilled and the solid residues are separated off by filtration. The solid residue is then dissolved in ammonia and reprecipitated with dilute hydrochloric acid at a pH of.

A mixture of 0.9 g of quinoxalic acid, 0.4 g of N, N-diethyl-m-toluidine (unit K, where R ₃ = CH ₃ , R = H, R ₅ = R ₆ = C ₂ Hc and ^R 7 = H) and 5 ml of acetic acid are rectified for five minutes and poured into ice and ammonia. The system is extracted twice with toluene, dried in the toluene using sodium sulfate, and then the toluene is evaporated. The residue is dissolved in chloroform and chromatographed on aluminum hydroxide using chloroform as the eluent. The solvent of the eluted fraction is evaporated and the material is recrystallized three times from toluene-petroleum ether and once from toluene. The product obtained, 1,1-bis (3-methyl

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4-diethylaminophenyl) -l- ₁ / H / -3 - / "! J7-furo / 3,4-b7 quinoxalΐη-3-οη, has a melting point between 181 and 186 ° C and a chloroform solution of this product gives on a with a phenolic resin or Silton clay or a combination of these two substances coated paper a brilliant green color.

The quinoxalic acid of Example 1 can can also be combined with other units and the following Table I shows a number of others Links.

Table I. Example unit

Substituents

colour

(K)

(K)

R ₃ = H

R ₄ = H

do.
do.
do.
do.

OC ₃ H ₇

Cl

R ₃ = OC ₂ H _C R "= H H

'5 * 4 "

^0C 6 ^H 13

do. do. do.

R ₅ = R ₆ = C ₂ H _{5 R} ^ _{= H}

do. do.

C ₂ H ₅

do. do. do.

do. do. do. do.

^R 5 ^{= R} 6 ^{= C} 2 ^H 5 ^R 7 ^{= H}

green

OC ₂ H ₅

blue

(K) R ₃ = CH ₃ R ₄ = H

H do.

R ₅ = CH ₃ Rg = benzyl R ₇ = H green H phenyl do. purple

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example Unit t ^R 8 = CH ₃ R _g
H Noun do 5 (L) ^R 8 = CH ₃ Rg
do.
do.
1-C ₃ H ₇ = CH ₃
H 6th (M) ^R 8 _λμ η
3 9
H
H
OC ₄ ed -Γ UD
= 1 / ρΠ r K
H
do.
^CH 3 10 ^{= H}
CH ₃
OCH ₃
H 7th (T) Rg = CH ₃
Phenyl Phenyl
H 8th (W) R ₁ ^{1 0C} 6 »13 9 (Z) R ₁₂ = H
do.

Color blue

blue green

blue blue

blue blue

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Example 10

Preparation of 1- (1-isopentyl-2-methylindol- -3-yl) -1- (2-ethoxy-4-diethylaminophenyl) -1-fllJ-3- £ lt] -furo [3,4b] -quinoxalin-3-one.

First, N, N-diethyl-m-phenetidine (K, where R ₃ = OC ₂ HS ₁ R ₄ = H, R ₅ = R ₅ = C ₂ H ₅ , R ₇ = H) with 2,3-quinoxalic acid ( I, where R ₁ = R ₂ = H) combined to give 2- (2-ethoxy-4-diethylaminobenzoyl) -3-quinoxalic acid. 0.1 mol of phenetidine and 0.1 mole of anhydrous aluminum chloride are added to 100 ml of tetrachloroethane at a temperature of about 5 ⁰ C. 0.05 moles of 2,3-quinoxalic anhydride are slowly added to this system while maintaining the temperature. The system is then allowed to ^{warm to 15 °} C. and stirred for 1 hour, after which it is poured over ice and a dilute hydrochloric acid solution. The pH of the system is adjusted to 2 and 10.5 g of a crystallized oil are separated off. This separated material is recrystallized several times from ethyl alcohol water and the product obtained has a melting point of 175-176 ° C.

The amounts of the individual elements for quinoxalic acid, calculated by elemental analysis, are in weight-I: C = 67.16 %; N = 10.68 *; H - 5.89 %.

A mixture of 2.0 g of quinoxalic acid, 1.14 g of 1-isopentyl-2-methylindole (M, where R ₃ = CH ₃ , R ₉ = C ₅ H ₁₁ , R ₁₀ = H) and 10 ml of acetic anhydride is added to a Temperature of about 50 ° C for about 1 hour and then poured into ice and ammonia. The system is extracted twice with toluene, dried in the toluene using sodium sulfate and the toluene evaporated. The residue is repeatedly recrystallized from toluene and has a melting point of 179-180 ° C. The product obtained is 1- (1-isopentyl-

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-1- (2-ethoxy - 4-diethylaminophenyl) -1- [kJ-3-00 ~ f ^uro D ^"4 ~ ⁱ 0 ^c h ^Inoxa l ⁱⁿ ~ 3-one and a solution of the product results in a phenolic resin or Silton-φοη-earth or a combination of these two substances coated paper a deep blue color.

The following amounts of the individual elements of this product in weight I were determined by an elemental analysis: C = 74.97; N = 9.71; H = 6.99.

The quinoxalic acid of Example 10 can also be combined with other units, for example obtained the compounds listed in Table II.

unit Tab lie II 4 ^{= H} W ^C 2 ^H 5 R ₇ = H colour example (K) C ₂ H ₅ do. do. green Blue 11 R ₃ = HR Substituents C ₃ H ₇ do. do. do. N (C ₂ H ₅ ) ₂ do. do. do. N (C ₄ Hg) ₂ do. do. green do. R ₄ = H ^R 5 ^{= R} 6 ^{= C} 2 ^H 5 R ₇ = H (K) do. do, do. CH ₃ green 12th R ₃ = CH ₃ do. do. C1 green do. do. do. H do. do. do. do. green Blue OC ₂ II ₅ green NO-

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example unit R ₈ = CH ₃ Substituents 13th (D do. R ₉ = CH ₃ do. Phenyl R ₈ = HR ₉ C ₄ H ₉ 14th (M) R ₈ = CH ₃ = Phenyl: do. ^C 2 ^H 5 do. H OC ₆ H ₁₃ do.

colour

purple

R ₁₀ = H blue do. blue CH ₃ blue OCH,

(T) R ₈ = CH ₃ R ₉ = C ₂ H ₅

^C 6 ^H 13 ^H

(W) R ₉ = CH ₃

Phenyl

blue

purple purple

(Z) R ₁₁ = OC ₂ H ₅ R ₁₂ = H

green Blue

Example 18

Preparation of 1,1-bis (3-chloro-4-diethylaminophenyl) -1-fH] -3- [H] -Euror3,4-b] quinoxalin-3-one.

First, m-chloro-N, N-diethylaniline (K, where R ₃ = Cl, R ₄ = H, R ₅ = R ₆ = C ₂ H _{5 md} R ₇ = H) with 2,3-quinoxalic anhydride (I, where R ^ = R ₂ = H) combined to give 2- (2-chloro-4-diethylaminobenzoyl) -3-quinoxalic acid. 0.2 moles

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Aniline and 0.2 moles of anhydrous aluminum chloride added to 250 ml of tetrachloroethane and stirred for 10 minutes. This system that initially cooled to 5 ° C 0.06 mol of 2,3-quinoxalic anhydride is added and the system is then stirred for 1-2 hours at 25 ° C. The mixture obtained is over 200 g of ice in Poured 20 ml of concentrated hydrochloric acid and then steam distilled. The obtained precipitate is several times recrystallized from acetonitrile and has a melting point of 193.5-194 ° C.

By means of an elemental analysis, the following amounts of the individual elements of quinoxalic acid in t calculated: C = 62.58; N = 10.95; H = 4.73; Cl = 9.24. The one in the The elemental amounts found in the above preparation were: C = 62.61; N = 11.00; H = 4.65; Cl-9.25

A mixture of 3.86 g quinoxalic acid, 2.1 gm-chloro-N, N-diethylaniline (K, where R ₃ = Cl, R ₄ = H, ^Κ 5 ^{= β} 6 ^{= ε} 2 ^Η 5 and R ₇ = H ) and 25 ml of acetic anhydride are heated in a melting tube to a temperature of 199 ° C. for 16 hours. The mixture is then poured into ice and ammonia and extracted with toluene. The toluene is dried using sodium sulfate, concentrated and chromatographed on aluminum hydroxide using chloroform and then ethyl acetate as the eluant. The solvent of the eluted fraction is evaporated and the material is recrystallized several times from the chloroform-petroleum ether. The product obtained 1,1-bis (3-chloro-4-diethylaminophenyl) -1- [H] -3- [H] -furo ^ 3,4-b] quinoxalin-3-one, has a melting point of 214- 216 ° C. and a solution of the same give a green-yellow color on paper coated with Silton clay and a green color on paper coated with phenolic resin.

The following amounts of the individual elements of the above product were determined by an elemental analysis S by weight calculated: C = 65.58; N = 10.20; H = 5.5O; C1 = 12.9O. The elemental amounts found in the above preparation were: C = 65.66; N = 10.21; H = 5.43; C1 = 13, O1.

The quinoxalic acid according to Example 18 can also be combined with other units, so that one for example, the compounds listed in Table III below are obtained.

Table III

example unit R ₃ = H
do. Substituents do. R ₇ = H
do. colour 19th (K) ^OC 2 ^H 5 R, = H Rr =
4 5
^0C 6 ^H 13 do. do. green
blue CH ₃ H do. do. green
blue V ^CH 3 do. green 20th (L) R ₈ = CH ₃ R ₉ = CH ₃ R ₁₀ = H green 21 (M) do. R ₉ -C ₂ H ₅ CH ₃ green
blue do. H OCH ₃ green
blue R ₈ = H
there. do. green
blue 22nd (W) R ₉ = CH ₃
Phenyl green
blue* Example 23

Preparation of 1- (1-ethyl-2-methylindol-3-yl) -1- (2-ethoxy-4-diethylaminophenyl) -1- [H] -3- £ H "] - for [3,4-bJ · quinoxaline-i-one.

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First, i-ethyl-2-methylindole (M, where Rg = CH ₃ , ^R 9 ^{= C} 2 ^H 5 ^{and R} 1O ^{= H} ^ ^{with 2} » ³ " ^{quinoxalic acid} anhydride (I ₁ where R ₁ = R ₂ = H) combined to obtain 2- (1-ethyl-2-methylindol-3-yl) -3-quinoxalic anhydride A mixture of 0.02 moles of the quinoxalic anhydride and 0.02 moles of the indole are placed on a steam bath for four hours The hardened mass is cooled and extracted with an ammonia solution, and the ammonia solution is washed with toluene. The ammonia solution thus washed is then acidified to precipitate this reaction product. The precipitate is filtered, dried and recrystallized several times from acetonitrile Melting point of 139-140 ° C.

The following amounts of the individual elements of quinoxalic acid in % By weight calculated: C = 70.18; N = 11.69; H = 4.77. The one in the The elemental amounts found in the above preparation were: C = 69.89; N = 11.58; H = 4.79.

A mixture of 1.0 g of quinoxalic acid, 0.6 g of N, N-diethyl-m-phenetiaine (K, where R ₃ = OCH ₃ R _{4 =} H, R ₅ = R ₆ = C ₂ H ₅ , R ₇ = H) and 7 ml of acetic anhydride are heated to 55 ° C. for 1 1/2 hours and then ice and ammonia are added, and then extracted with toluene. The toluene is dried using sodium sulfate and then evaporated. The residue is recrystallized from acetonitrile and has a melting point of 213.5-214.5 ° C. The product obtained, 1- (1-ethyl-2-methylindol-3-yl) -1- (2-ethoxy-4- diethylaminophenyl) -1- (V | -3- £ H] -furo [3,4-b] -quinoxalin-3-one, produces a blue color on paper coated with phenolic resin or Silton clay or a combination of these two substances .

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It should be noted that the product obtained from this Example 23 is the same like the second product of the preceding example 14, but produced by a different process.

The quinoxalic acid of Example 23 can also be linked to other units. In the Table IV below gives a number of further compounds.

Table IV

example unit R ₃ = CH ₃ Noun do H ₅ R ₇ = H colour 24 (K) ^R 8 ^{= CH} 3 R ₄ = HR = R- = C _?
O 0 L green 25th (L) do. R ₉ = CH ₃ Red ^C 2 ^H 5 Phenyl Red R ₈ = CH ₃ H 26th (M) do. R ₉ = C ₂ H ₅ R 10 ^{= H} purple do. H CH ₃ 3 Red do. do. ^C 6 ^H 1 do. do. OCH ₃ 13th Red Phenyl do. OC ₆ H ^R 8 ^{= CH} 3 ^C 2 ^H 5 H purple 27 (T) R ₉ = CH ₃ R ₉ = C ₂ H ₅ purple 28 (W) Red

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Example 29

Preparation of 1,1-bis (3-methyl-4-diethylaminophenyl) -6,7-dimethyl-1- [jf] -3- [H] ~ furo [3,4-b3 quinoxalin-3-one.

First, N, N-diethyl-m-toluidine (K, where R ₃ = CH ₃ , R ₄ = H, R ₅ = R ₆ = C ₂ H ₅ , R ₇ = H) with 6,7-dimethyl-2 , 3-quinoxalic anhydride (I, where R ₁ = R ₂ = CH.,) Combined to give 2- (2-methyl-4-diethylaminobenzoyl) -6,7-dimethyl-3-quinoxalic acid. A mixture of 0.1 mol of toluene and 0.1 mol of anhydrous aluminum chloride is stirred in 100 ml of tetrachloroethane. The mixture is cooled to less than 10 ° C. and 0.02 mol of the 2,3-quinoxalic anhydride is slowly added. The mixture is stirred for 2 hours and then poured into ice and concentrated hydrochloric acid and steam distilled. The distillate is made basic and filtered. The filtrate obtained is redissolved in dilute hydrochloric acid, the pH is adjusted to 3.5 and the system is filtered again. The obtained filtrate is dissolved in an ammonia solution and the pH is adjusted to 3.0. The system is filtered again and the dried residue is quinoxalic acid.

A mixture of 1.0 g of the quinoxalic acid, 0.45 g of N, N-diethyl-m-toluidine (K, where R ₃ = CH ₃ , R ₄ = H, R ₅ = R ₆ = C ₂ H ₅ , R ₇ = H) and 10 ml of acetic anhydride is rectified for 1 hour and poured into ice and ammonia. The system is extracted twice with toluene, dried using sodium sulfate in the toluene, and

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then the toluene is evaporated. The residue is dissolved in chloroform and prepared using Chloroform as eluent chromatographed on aluminum hydroxide. The solvent of the eluted Fraction is evaporated and the material is recrystallized three times from toluene-petroleum ether and once from toluene. A solution of the product obtained namely 1,1-bis (3-methyl-4-diethylaminophenyl) -6,7-diethy 1-1 - [h] -3- [h] -furo [Ϊ5,4-b] quinoxalin-3-one on one coated with phenolic resin or Silton clay or a combination of these two substances Paper a green color.

The quinoxalic acid of Example 29 can also be linked to other units. The following Table V shows some such additional compounds.

Table V

example unit R ₃ = OC ₂ H ₅ Substituents > 6 2 E colour 30th (K) Cl R ₄ = H Rj do. . R ₇ = H green NO ₂ do. do. do. green R ₈ = CH ₃ do. do. yellow 31 (L) do. R ₉ = CH ₃ blue V ^CH 3 Phenyl ^R 10 ^{= H} blue 32 (M) Phenyl R ₉ = C ₂ H ₅ do. blue
green CH ₃ do. CH ₃ green do. H OCH ₃ green
blue do. green
blue

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Example unit Suhstituenten color

33 (T) R ₈ = CH ₃ R ₉ = C ₂ H ₅ blue

34 CW) R ₉ = CH ₃ blue

Phenyl

35 (Z) R ₁₁ = OCII ₃ R ₁₂ = II purple

purple

do. 1 CII 3 do. ^C 2 ^H 5 Example 36

Production of 1,1-bis (1,3, S-trimethylpyrr- ^ -dichloro-i- [n] -3- [II] -furo [3,4-b] quinoxalin-3-one.

18.5 g of dihydroxysuccinic acid are added to a solution of 25.1 g of 4,5-dichloro-o-phenylenediamine in each case 220 ml V / water and ethanol are added and the mixture is stirred for 5 minutes, acidified with hydrochloric acid and the reaction product, namely 6,7-dichloro-2,3-quinoxalic acid, filtered off.

A mixture of 0.6 g of the quinoxalic acid and 0.6 g of 1,2,5-trimethylpyrrole (L, where Rg = R ₉ = CH ₃ ) is brought together in a solution of hydrochloric acid to give 1,3,5-trimethylpyrrole -3-yl) -6,7-dichloro-1- [H] -3- [H]

-tn-quinoxalin-S-one to get which on a phenolic resin coated paper gives an orange color.

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Example 37

A mixture of 0.6 g of the quinoxalic acid prepared according to Example 36 and 0.75 g of 1-ethyl-2-methylindole (M, where R _g = CH R ₉ = C ₂ II ₅ ) to 1,1-bis (1- ethyl-2-methylindol-3-yl) -6,7-dichloro-1- [H] -3- [H] -Euro [3,4-bjquinoxalin-3-one, which is coated with phenolic resin Paper turns purple.

Example 38

Preparation of 1,1-bis (2-methyl-4-diethylaminophenyl) -6,7-dimethyl-1 - [} l3-3- |} l "] - furo [j5,4-b] quinoxalin-3-one.

25 g are added to a boiling solution of 25 g of 4,5-dimethyl-o-phenylenediamine in 500 ml of water. Hydrochloric acid gas is passed through this mixture. The mixture is cooled and becomes a solid product separated by filtration. The separated material is dried, dissolved in 150 ml of acetic acid and 15 Rectified for minutes. The system is cooled and filtration gives 6,7-dimethyl-2,3-quinoxaline anhydride separated with a decomposition point of 241 ° C.

A mixture of 0.6 g of the quinoxaline anhydride and 0.9 g of N, N-diethyl-m-toluidine (K, where R ₃ = CH ₃ , R ₄ = H, Rc = R _n = C ₉ Hj. R ₇ = H) in 10 ml of acetic anhydride is rectified for 1 hour, it is added dilute ammonia, the mixture is extracted with toluene and the reaction product, namely 1,1-Ms (2-methyl-4-diethyl-aminophenyl) -6,7- dimethyl-1-Hj% oro (3,4-b] quinoxalin-3-one is isolated, and the product obtained gives a green color on paper coated with phenolic resin.

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Example 39

The procedure of Example 38 is followed

repeatedly using 0.6 g of quinoxalic anhydride and 1.0 g of Ν, Ν-diethyl-m-phenetidine (K, where R ₃ = OCH ₃ , R ₄ = H, R ₅ = R ₆ = C ₂ H ₅ , R ₇ = II). The reaction product is 1,1-bis (2-methoxy-4-diethylaminophenyl) -6,7-dimethyl-1- [H] -3- [V] -furo [1,4-b] quinoxalin-3-one and produces a green-blue color on paper coated with phenolic resin.

Other compounds analogous to those of Examples 38 and 39 above are as follows:

Table VI

example unit R. ₃ = CH 3 3 Substituents V ^R 6 -C ₂ H 5 R ₇ = C 4 ^H 9 40 CK) do * 5 R ₄ = H do. N < ^C 4 ^C 6 ^H 1 do. do. H R. ₃ = oc 2 ^H do. V ^R 6 -C ₂ H 5 R ₇ = C 6 ^H 1 41 CK) R ₄ = H

do. do. do.

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Claims (2)

2520H8 Claims; ΛΛ Chromogenic compound characterized by the Structural formula V / Y wherein X is one of the groups K, L, M, T, W or Z, and Y is one of the groups K, L, M or T, where ; L. R ₈ N ^R 9 50988W1126 2520U8 and in which R., Rp, R ₃ , R ₄ and R ₇ independently of one another are hydrogen, chlorine or a nitro, alkyl, alkoxy or dialkylamino radical; R ₅ and R _{g are} hydrogen or a phenyl, benzyl or alkyl radical, provided that when R ₅ or R _{ß is} a phenyl or benzyl radical, the other group is hydrogen or a methyl radical; R _{ß is} hydrogen or a phenyl, alkyl or alkoxy radical; Rq is hydrogen or a phenyl or alkyl radical; Rj _{0 is} hydrogen or an alkyl or alkoxy radical; R _{11 is} an alkoxy radical; and R _{12 is} hydrogen or a methyl or ethyl radical; all alkyl and alkoxy groups having fewer than seven carbon atoms. 2. pressure-sensitive recording material, characterized in that its color formation system contains a chromogenic quinoxaline compound and an acidic reagent therefor. May 2nd 1975 509884/1126