DE2631040A1 - PROCESS FOR THE PRODUCTION OF BASIC OXAZINE DYES - Google Patents

Description

Process for the preparation of basic oxazine dyes

The invention relates to a novel process for the preparation of basic oxazine dyes.

It is known that basic oxazine dyes are produced in two stages by going primarily from aromatic. Amines produces nitroso compounds, isolates them and uses them Aminophenols condensed. However, these known processes have the disadvantage that they are carried out in separate process steps and that the handling of the toxic nitroso compound can only be done with careful observance of precautionary measures, as they are with many Makes people stronger skin damage.

In order to remedy these disadvantages, DOS 1.569.604 proposes basic oxazine dyes in a one-step process without isolating the nitroso compound in such a way that starting from an aminophenol ether this can be converted into aqueous-alcoholic solution nitrosated at a temperature of 0 to H-3 ° C and then the nitroso compound in

na ft Q /.-/ 1 Π7

Suspension condensed with an aminophenol to form the oxazine dye.

Another novel one-step process for the production of oxazine dyes has now been found, compared to that the one described in the aforementioned German Offenlegungsschrift The method has the advantage that it can surprisingly be carried out at room temperature, which is more rational and results in a considerable saving of energy and an increase in the synthesis capacity.

The new process according to the invention is characterized in that basic oxazine dyes of the general Formula 1)

• θ

- ^ 2

N "

^L i I. Il I! "3

x ° (D

manufactures in what

R, R2 and Ro alkyl with 1 to 4 carbon atoms,

R ₁ H or alkyl having 1 to 4 carbon atoms, or

R and R, or R ^ and R- together with the amine nitrogen too

form a saturated 5- or 6-membered ring, optionally containing further heteroatoms, such as __ - _ e.g. a morpholine, piperidine or pyrrolidine

ring,

R ^ H or methyl and

X ^ an anion, preferably a chlorine ion or ZnCL, -

Ion,

4/107

" ³ - 2631OAO

mean by adding a compound of the formula (2)

1 L U (2)

V "'

wherein R, independently of one another, and R-. and R, the under Formula (1) have given meaning, in a cyclic ether, suIfolan or alkyl-substituted amide, optionally mixed with water or an aliphatic alcohol, nitrosated and the resulting suspension containing the nitroso compound without intermediate isolation of the same with a Aminophenol of formula (3)

N ^ ²

³ (3)

)H

in which R ₂ and R ~ have the meaning given under formula (1), condensed. After the condensation, the dye precipitates or is advantageously precipitated, expediently in the form of the chloride or zinc chloride salt.

Particularly good results are obtained with compounds of the formulas (2) and (3) in which R, R-, R ₂ and R- are each the C ₂ H, group and R, is hydrogen.

The method according to the invention, which is characterized by its great simplicity and economy, proceeds in detail such that the compound of formula (2) initially

9-8 84/1076

is nitrosated. This takes place at room temperature, approximately between 20 and 25 ° C, in a solvent that consists of either a cyclic ethers, such as dioxane, tetrahydrofuran or suIfolane (cyclic sulfone), or from an alkyl-substituted one, in particular Ν, Ν-disubstituted acid amide, such as dimethylformamide, Dimethylacetamide, N-methylpyrrolidone or hexamethylphosphoric acid triamide, consists or a mixture of one of these solvents with water or a low molecular weight alcohol, such as methanol, ethanol, propanol, isopropanol or glycol. Using a mixture of solvents, such as one cyclic ether with water, such as, in particular, a mixture of dioxane / water, can be added to 100 parts total volume between 70 and 99 parts of dioxane and 30 to 1 part of water come. The best relationship, also from an economic point of view, lies in azeotropic mixing ratio. In the case of the dioxane / water azeotrope, this is a composition of 82:18.

The nitrosation that occurs with the usual nitrosating agents, such as sodium nitrite, can also be carried out in the presence of an acid, in particular hydrochloric acid or Sulfuric acid, which acid is also generally sufficient to remove the reaction mixture during the subsequent condensation keep pissed off.

Particularly suitable compounds of the formula (2) are:

60 9884/107 B.

l-dimethylainino-phenyl-3-methyl ether, 1-diethylaminophenyl-3-methyl ether, l-dipropylaminophenyl-3-butyl ether, l-ethylmethylaminophenyl-3-methyl ether, 1-N-pyrrolidinophenyl-3-methyl ether, l-N-piperidinophenyl-3-ethyl ether, l-N-morpholinophenyl-3-ethyl ether and l-ethylamino-o-methylphenyl-S-ethyl ether.

The condensation of the resulting nitroso compound, which cannot be isolated, with the compound of the formula (3), which is advantageous in a 5- to 10% excess, based on the Compound of formula (2) is added, is expediently carried out in the same solvent as that of the nitrosation, by prior to the addition, if necessary, the pH value is blunted to approx. up to 4 by adding buffer substances. the actual condensation to the oxazine dye of formula (1) takes place at an elevated temperature, in particular between 70 and 75 ° C.

Compounds of the formula (3) that can be used are, for example:

3-dimethylaminophenol,

3-diethylaminophenol,

3-dibutylaminophenol,

3-N-pyrrolidinophenol,

3-N-piperidinophenol,

3-N-morpholinophenol and

3-ethylmethylaminophenol.

809884/1076

- 6 - 2631OAO

The solvent for the nitrosation and the subsequent condensation can then be recovered and be added to the process anew. It is particularly advantageous if an azeotropic mixture is used.

In many cases, the oxazine dye of the formula (1) falls practically quantitatively in crystalline form and in very good purity, in other cases isolation takes place through Distilling off the solvent and precipitating the dye from the solution, so that in both cases a dye of high color strength. In addition, no special isolation and cleaning processes are necessary.

The process according to the invention gives oxazine compounds of formula (1), which are known as such and which are suitable for dyeing or printing, e.g. Cellulose fibers, silk, leather or fully synthetic fibers such as acetate silk, polyamide fibers or acid modified polyamide or Polyester fibers, but in particular polyacrylonitrile as well as fibers obtained from polyvinylidenecyanide.

In the following example which illustrates the invention without limiting them to this, the temperatures are given in degrees Celsius.

6098a4 / 1Q7S

example

160 ecm of dioxane with 18% water content are placed in a 750 ccm flask with a dropping funnel and stirrer, and then
59.1 g of 3-diethylaminophenetol of the formula

C ₂ H ₅

registered and

25.8 g of 100% hydrochloric acid were added. The temperature is kept at about 20 °. The nitrosation is then carried out over the course of 30 minutes by adding 23 g of sodium nitrite, the temperature being maintained between 20 and 25 ° with external cooling. The resulting yellow-brown solution is allowed to stir at about 20 to 25 ° for 30 minutes. By adding approx.
2.4 g of soda the pH is blunted to 3.0 to 3.5.

Be in a separate 750 ccm flask with a dropping funnel, stirrer and reflux condenser
175 ecm of dioxane with 18% water content and 55.0 g of 3-diethylaminophenol of the formula

- ^ OH
registered. The mixture is heated to 70 to 75 ° and left within

609m / 1Q7S

3 hours at this temperature with thorough stirring, the nitrosation suspension flow evenly. It is then allowed to cool to about 50 ° C. and about 5.7 g of hydrochloric acid are added, with the pH is adjusted to about 2.5. At one temperature from about 50 ° C 25 g of zinc chloride and 20 g of table salt are added. The dye of the formula

C ₂ H ₅

ZnCl,

crystallizes in green shredding prisms.

It is cooled to 25 ° C for ₅ stirred for one hour at this temperature, suction filtered and dried at about 100 ° C.

If the procedure is analogous to that given in the example, but instead of 160 ecm water-containing dioxane is used equal amounts of suIfolane or tetrahydrofuran, N-methylpyrrolidone, hexamethylphosphoric acid triamide or dimethylacetamide, the dye is thus obtained in an equally good yield (80 to 85%) and quality.

609884/1075

Claims (9)

Claims 1. Process for the preparation of basic oxazine dyes Formula 1) X ⁹ (DLR ₄ ^ ^ "ΊΓ ^ν R, Ro and Ro alkyl with 1 to 4 carbon atoms, R ₁ H or alkyl, having 1 to 4 carbon atoms, or R and R, or R "and R., together with the amine ticks off one too form a saturated 5- or 6-membered ring, optionally containing further heteroatoms, R, H or methyl and X ^ an anion mean, characterized in that a compound of the formula »(2) I R ^ Y (2) ^R 4
wherein R, independently of one another and R..and R, have the meaning given under formula (1), in a cyclic ether, suIfolane or alkyl-substituted amide, optionally mixed with water or an aliphatic alcohol, nitrosated and the resulting suspension containing the Nitroso compound without intermediate isolation of the same with a 609884/107 Aminophenol of formula (3) N ^{L K} 3 (3) OH where R ^ and R- have the meaning given under formula (1), condensed. 2. The method according to claim 1, characterized in that that compounds of the formulas (2) and (3) are used, in which R, R ^, Rp and R- each represent the C-H, group and R, hydrogen means. 3. The method according to claims 1 and 2, characterized in that that the nitrosation is carried out in the presence of an acid at room temperature. 4. The method according to claims 1 to 3, characterized in that that as a solvent a mixture of water with a cyclic ether in a ratio of 1 to 30 parts of water and 70 to 99 parts of cyclic ether is used. 5. The method according to claim 4, characterized in that that an azeotropic mix ratio is used. 6. The method according to claims 4 and 5, thereby marked draws that a dioxane / water azeotrope is used. 609884 / 107S 26310A0 7. The method according to claims 1 to 6, characterized in that that the condensation is carried out at an elevated temperature. 8. The method according to claim 7, characterized in that that the condensation is carried out at 70 to 75 ° C. 9. According to the method of claims 1 to 8 obtained oxazine dyes of the formula (1). 609 8-8 4 / tO 7 5