DE2448429A1 - PROCESS FOR THE PREPARATION OF 4-AMINO-3-METHYL-N-SUBSTITUTED OR -UNSUBSTITUTED ALKYLANILINES - Google Patents

Description

PATENT LAWYERS A. GRUNECKER

DIPL-INOi.

H. KINKELDEY

OR.-INQ.

W. STOCKMAIR

_. / Λ · ΛΛ DR.-INQ. AOE (CALTECH)

£ 4 4 8 4 2 9 K. SCHUMANN

. DR. REIR. NAT. · DIPL.-PHYS.

P. H. JAKOB

DIPL.-ΙΝΘ.

G. BEZOLD

DR. RER. NAT. ■ DIPL.-CHEM.

MUNICH

E. K. WEIL

DR. RER. OEC. INQ.

LINDAU

8 MUNICH 22

MAXIMILIANSTRASSE 43

October 10, 1974 P 8615-sh

SAWKIO CHEMICAL CO., LTD.

Osaka Bldg., Ho. 2, KyobasM "1-Chome, Chuo-Ku, Tokyo, Japan

Process for the preparation of 4-amino-3-methyl-N-subs-titu = ated or unsubstituted alkvlanilines

The invention relates to a process for the preparation of 4-amino-3-methyl-N-substituted or unsubstituted Alkylanilines, in particular a process for the preparation of these alkylanilines from 4-amino-3-methyl-nitrobenzene, in which the amino group of the 4-araino-3-methyl-nitrobenzene used as the starting compound is protected, e.g. by toluenesulfonylation, phthalylation or acetylation, the nitro group of the nitrobenzene is hydrogenated and then alkylated, and the intermediate product obtained is subjected to hydrolysis. the Reaction products can optionally be made using inorganic or organic acids converted into salts will.

Ν, Ν-disubstituted p-phenylenediamines are important

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TELEPHONE (ΟΒβ) 23 OB 62 ■ TELEX OE-29 38Ο TELEQRAMME MONAPAT

represent bindings as color developers for color photography, where in particular the p-phenylenediamines with; a methyl group special importance in o-position to the primary amino group comes to.

Various processes are already known for the preparation of 4-amino-3-methyl-N-substituted alkylanilines, which are commercially available color developers for color photography. Examples of this are the processes described in "Journal of the American Chemical Society" 21 0951) 3100 -3125, as well as the processes described in the published JA-PA 11 534/72 and 11 535/72.

m-Toluidine, which is used as the starting material for the aforementioned method is produced by nitration of toluene and reduction of the m-nitrotoluene obtained. In practice it represents however, m-nitrotoluene is only a by-product that occurs in the nitration stage of the toluene is only obtained in an amount of about 3 percent. The yield of m-nitrotoluene is thus too low, and supply and demand for this product are often not in balance. In these circumstances it acts in the aforementioned process for the preparation of p-phenylenediamines using m-toluidine as a starting compound from the viewpoint of cost and the nature of Starting compound is not a technically expedient and reliable process.

An object of the invention is therefore to provide the aforementioned To overcome disadvantages and a cheaper, more advantageous process for the preparation of 4 ~ amino ~ 3-methyl-N-substituted or to provide unsubstituted alkyl anilines.

The invention therefore relates to a new method of production of 4-amino-3-methyl-N-substituted or unsubstituted Alkyl anilines, which is characterized in that 4-amino-3-methyl-nitrobenzene of Fouiel I.

509820/1185

- T "-

(D

NH,

with an acylating or sulfonylating agent for the acylation and / or sulfonylation to give a compound of the general formula II

(II)

R,

subjects, is in the E. a hydrogen atom or an acyl group, 'and Rp represents an acyl or sulfonyl, or IL and Rp zusa mm s represent a divalent acyl radical; the nitro group of the compound of general formula II with hydrogen in the presence of a metal hydrogenation catalyst to form a compound of general formula III

NH,

(HD

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_ *, .. 2448 ^ 29 H.

in which E ^ and Rp have the aforementioned meaning, reduced, substituted the amino group of the compound of the general formula III with an alkylating agent from the group consisting of alkyl halides Alkyl halides and alkylene oxides of the alkylation to form a compound of the general formula IV

(IV)

subject, in which E and E "have the aforementioned meaning, E denotes an alkyl group or a substituted alkyl group, and E. denotes a hydrogen atom, an alkyl group or a represents substituted alkyl; and the connection of general Formula IV the hydrolysis to form a compound of the general formula V

(V)

subject, in which R ^ and E. have the aforementioned meaning.

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. _ ^ 2448A29

As previously described, the invention relates to a process for the preparation of 4-amino-J-methyl-N-substituted or unsubstituted alkyl anilines using - ^ - of A — Amino-J-methyl-nitrobenzene, which is technically and economically is easily accessible. The process according to the invention is represented by the following reaction scheme

(Acylation

or
Sulfonylation)

(I)

CH,

(Reduction)

(Alkylation)

CH,

(III)

R.

(Hydrolysis")

CH,

(IV)

(V)

in which IL is a hydrogen atom or an alkyl radical, for example the group -COGH ₅ : Rp is an acyl radical, for example the group -COCH-, or a sulfonyl radical, for example the group -SOp- ~ \ L3- ^CH ; o, or R. and Rp together represent a di-acyl radical, for example the group

5 0 9 8 2 0/1185

6 -

O-- form; R ₇ . an alkyl radical, for example an unsubstituted lower alkyl radical with 1 to 3 carbon atoms, such as an ethyl group, or a substituted alkyl radical, such as a hydroxyalkyl radical with 2 to 3 carbon atoms, for example the group _{-C 2} H ₄ OH or -C ₇ H ₆ OH, the group -C ₂ H ₄ HHoO ₂ CH _5, or -C ₂ II ₄ SO H; and R _{4 is} a hydrogen atom, an unsubstituted alkyl radical, for example a lower alkyl radical with 1 to 3 carbon atoms, such as a methyl, ethyl or propyl group, or a substituted alkyl radical, for example an iron hydroxyalkyl radical with 2 to 3 carbon atoms, such as Group -CpH ₄ OII, means.

To protect the amino group in the first stage, i.e. the acylation or sulfonylation, the acetylation becomes strongest preferred; however, other protective groups, such as p-toluenesulfonyl groups or phthalyl groups. be used.

During the acetylation, the 4-amino-3-methyl-nitrobenzene (i) after dissolving in a suitable solvent such as tetrahydrofuran with acetic acid, and then dropwise with acetic anhydride added to complete the reaction. The reaction takes about 60 to 90 ° C at temperatures 1 to 6 hours. Other acylations or sulfonylations can be carried out in a similar manner.

The hydrogenation in the second stage, ie the reduction stage, is carried out in a simple manner using hydrogen at a pressure of about 15 to 80 kg / cm, preferably 50 to 80 kg / cm, at reaction temperatures of about 50 to 120 ° C., preferably 100 to 120 ⁰ C, carried out for a period of about 1 to 3 hours in the presence of a metal hydrogenation catalyst, such as Raney nickel. If necessary, alkyl aldehydes such as acetaldehyde used in the next step, that is, the alkylation step, may be incorporated into the reaction system from the beginning.

In the third stage, i.e. the alkylation stage, a Al ^ yl ^ alogenid, such as ethyl chloride, used as an alkylating agent

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BATH ORIGINAL

be turned. Substituted alkali halides, such as ethylene chlorohydrin, or "ß-methanesulfonamidoethyl chloride, or alkylene oxides, such as ethylene oxide, can be used as substituted alkylating agents. The alkylation is carried out under normal pressure or under increased pressure, the 4-alkylamino ~ 3 ~ methyl-H-substituted or unsubstituted alkyl aniline is formed without difficulty. The reaction conditions vary to a large extent depending on the starting compounds used; however, the person skilled in the art can select suitable ones Conditions based on similar alkylations no difficulties.

In the fourth stage, ie the hydrolysis stage, typical examples of hydrolyzing agents are hydrochloric acid and sulfuric acid, for example about 40 to 60 percent by weight sulfuric acid, preferably 50 percent by weight sulfuric acid. The hydrolysis is carried out at temperatures of about 80 to 120 ^° C. for a period of about 3 hours using such a hydrolysis agent; furthermore, bases, for example alkali, can optionally be used in order to make the reaction system alkaline. Alternatively, other inorganic or organic acids such as hydrobromic acid, sulfurous acid, p-toluenesulfonic acid or oxalic acid can optionally be used. As described above, the process of the invention consists essentially of four reaction steps.

The examples illustrate the invention. Unless otherwise stated, All parts, percentages, proportions and other information are based on weight.

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- 8 ■ - Example 1

A. Preparation of 4-acetamino-3-methyl-nitrobenzene:

349.6 g (2.3 mol) of 4-amino-3-methyl-nitrobenzene are dissolved in 500 g of tetrahydrofuran. This solution is washed with 5OO g of acetic acid and then added dropwise with 5OO g (3.5 mol) of acetic anhydride while heating at 70 to 80 ⁰ C. After the addition of acetic anhydride is complete, the entire reaction system is refluxed for 3 hours and then allowed to cool. Crystals separate out, which are filtered off and dried. 367 g of the desired compound of i ^{1 are obtained} . 200 to 202 ° C.

B. ■ Production of 4-acetamino-3-methylaniline:

19.4 g (0.1 mole) 4-acetamino-3-methyl-nitrobenzene, 30 g Dimethylformamide and 1 g of freshly made Raney-I nickel are placed in an autoclave. After getting the autoclave

ρ has applied a hydrogen pressure of 50 kg / cm, the reaction is carried out ^{at 60 to 120 ° C. with stirring.} Immediately thereafter, the reaction mixture is removed and after having the Raney nickel is still hot removed, the reaction product is poured into 100 ml methanol to give the desired 4-acetamido-3-methylaniline melting at 140 to 14O, deposited 5 ° C . Yield 16.0g.

Analysis: C H N

found: 65.2 7.5 17.1 calc .: 65.83 7.37 17.06

Ct 'production of 4-acetamino-3-methyl-N-ethylaniline:

30 g 4-acetamino-3-methylaniline, 12.1 g acetaldehyde (90 percent), 2 g sodium acetate, 5 g freshly made Reney nickel and 80 ml of methanol are placed in an autoclave,

which is then subjected to a hydrogen pressure of 80 kg / cm

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68 , 72 8th, 1 14, 1 68 8th, 39 14, 57

will. The reaction takes place with stirring at room temperature (20 to 30 ° C) 2 to 3 hours. The termination of the reaction is indicated by the cessation of the hydrogen uptake. Much removal of the reaction solution and removal of the Raney nickel, the methanol is distilled off, whereby one receives white crystals. When recrystallizing from ethyl acetate, 30 g of white crystals with a melting point of 102 ° to 103 ° C. are obtained.

Analysis: GH N_

found: ber.:

D. Preparation of 4-acetamino-3-methyl-N- (ß-methanesulfonamidoethyl ) -N-ethyl aniline:

A mixture of 57.6 g ■ 4-acetamino-3-methyl-N-ethylaniline, 52 g ß-methanesulfonamidoethyl chloride, 27.7 S sodium hydrogen carbonate, 70 g of water and 70 ml of methanol is 5 hours held under reflux. The methanol is then distilled off under reduced pressure. When the reaction mixture is mixed with water, an oily product separates out. This oily product is poured into ethyl acetate and cooled. This gives 64 g of white 4-acetamino-3-methyl-li- (ß-methanesulfonamidoethyl) -N-ethylaniline from 104 to 105 ° C.

Analysis:

found : ber.:

E. Production of 4-amino-3-methyl-N- (ß-methanesulfonamidoethyl) -N-ethylaniline sesquisulfate * HpO: '

A mixture of 60 g of 4-acetamino-3-methyl-N- (ß-methanesulfonamidoethyl ) -N-ethylaniline, 47 g sulfuric acid and 36 g water is stirred at 100 to 120 ° G for 3 hours. After adding 65 ml Methanol and 140 ml isopropanol, the reaction mixture is

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C. 7th H 1 3 , 36 53.57 7th , 44 1 3 , 41 53.65 , 40

- ΊΟ -

2U8429

cooled with stirring, the desired 4-amino-3-methyl-N- (ß-methanesulfonamidoethyl) -N-ethylaniline-BeGauisulfat'HpO separating out. After filtering off and drying the product are obtained 73 g of white crystals, melting at 128 to 13O ⁰ C. When performing a Hischschmelzpunkts with an authentic sample, prepared by recrystallization of a commercially available product from isopropanol, no melting point depression is observed. The IR absorption spectra of the two products correspond completely.

Analysis:

C. , 9 6th ti 9 N found : 32 , 0 6th , 0 9 , 7 ber .: 33 , 0

Example 2

A. Preparation of 4- (N-p-Toluenesulfonyl) -amino-3-methylnitrobenzene

A mixture of 152 g (1 mol) of 4-amino-3-methyl-nitrobenzene, 80 g of sodium carbonate and 500 g of water is admixed with 230 g (1.2 mol) of p-toluenesulfonyl chloride while stirring. After 3 hours of reaction at 70 ° C to obtain 290 g of 4- (Np-toluenesulfonyl) amino-3-methyl-nitrobenzene from I ^1, 173 to 174- ° C

B. Preparation of 4- (N-p-Toluenesulfonyl) -amino-3-methylaniline

30.6 g (0.6 mol) 4- (N-p-toluenesulfonyl) -amino-3-methyl-nitrobenzene, 1 g of freshly prepared Raney nickel and 60 ml of tetrahydrofuran are placed in an autoclave. After the

If the autoclave has been subjected to a mass pressure of 60 kg / cm, the reaction is carried out at 5 ° to 100 ° C. with stirring. To. At the end of the reaction, the Raney nickel is removed from the reaction solution and the tetrahydrofuran is distilled off. Brown M - (Np-toluenesulfonyl) amino-3-methylaniline is obtained which, after recrystallization from ethyl acetate, gives 24 g of yellow-brown crystals with a melting point of 147 ° to 148 ° C.

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Analysis: CHN

found: 60.4 5.9 10.5 calc .: 60.84 5.83 10.13- -----

C. Preparation of 4- (N-p-toluenesulfonyl) -amino-3-methyl-N-ethylaniline

An autoclave is charged with 23 g of 4 ^ (Np-toluenesulfonyl) -amino-3-methylaniline, 6.1 g of acetaldehyde (90 percent) and 0.8 g of anhydrous sodium acetate and then with a hydrogen pressure of 80 to 90 kg / cm applied. The reaction is carried out at 20 to ^ 0 ⁰ G. After the reaction has ended, the precipitated crystals are dissolved by adding 100 ml of tetrahydrofuran, and after the Raney-Niekel has been removed, methanol and tetrahydrofuran are distilled off, crystals of 4- (Np-toluenesulfonyl) -amino-3-ynethyl-N-ethylaniline excrete. After recrystallization from ethyl acetate, 20 g of white crystals are obtained

F. 162 to 163 ° C. G ,8th 6th H 9 N Analysis: 62 , 13 6th , 6 9 , 3 'found: 63 , 62 , 20 ber .:

D. Preparation of 4-amino-3-methyl-N- (ß-methanesulfonamidoethyl) -N-ethylaniline sesquisulfate · HpO

A mixture of 7 g of 4- (N-p-toluenesulfonyl) -amino-3-methyl-N-ethylaniline, 4 g of ß-methanesulfonamidoethyl chloride, 2.1 g Sodium hydrogen carbonate, 16 g of water and 30 ml of methanol Heated under reflux for 5 hours. After one with 16 g of sulfuric acid has added, the whole reaction system is again held under reflux. After getting the reaction solution has evaporated to half of its original volume, 300 ml of isopropanol are added. Here are divorced Crystals from which are filtered off and dried. This gives ^, 5 g of 4-amino-3-methyl-N- (ß-methanesulfonamidoethyl) -N-

• 509820/1 185

ethylaniline sesquisulfate «H ₂ 0 from P. 128 to 13O ⁰ G.

When performing a mixed melting point on an authentic sample made by recrystallizing a commercial product from isopropanol, none
Melting point depression observed. The IR absorption spectra of both products are completely identical.

Example 3

A. Preparation of 4-acetamino-3-methyl-N- (ß-hydroxyethyl) -N-ethylaniline

A mixture of 15.2 g (0.08 mol) of the ^ -acetamino ^ -methyl-N-ethylaniline obtained in Example 1C, 4.2 g (0.09 mol)
Ethylene oxide and 50 ml of ethanol is sealed in a
Heated autoclave for 1 hour at 120 to 13O ⁰ C. The ethanol is then distilled off, crystals of 4-acetamino-3-methyl-N- (ß-hydroxyethyl) -N-ethylaniline being obtained. After recrystallization from ethyl acetate to obtain 18.5 g of white crystals, P. 121-122 ⁰ C.

Analysis: C ' H

found : 66 , 0 8th , 53 11 , 5 ber .: 66 , 07 8th 11 , 86

B. Preparation of 4-amino-3-methyl-N- (ß-hydroxyethyl) -N-ethylaniline sulfate

23.6 g (0.1 mol) of 4-acetamino-3-methyl-N- (β-hydroxyethyl) -N-ethylaniline are dissolved in 30 g of 50 percent sulfuric acid. The reaction system is heated to 80 to 100 ° C. for 5 hours with stirring, then poured into 300 ml of isopropanol and stirred while cooling. The deposited crystals are filtered off and dried. 22.2 g of 4-amino-3-methyl-N- (β-hydroxyethyl) -N-ethylaniline sulfate from I ^{1 are obtained} . 154 to 155 ⁰ C.

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When performing a Mi ochs Chin elzpunkt with an authentic Sample obtained by recrystallizing the commercial product made from isopropanol, there will be no pain point depression observed. The IR absorption spectra of both products are completely identical.

Example 4

Production of ^ - Amino - ^ - methyl-N- (ß-hydroxyethyl) -N-ethylaniline sulfate

30 g (0.1 mol) of 4- (Np-toluenesulfonyl) -amino-3-methyl-N-ethylaniline (received in Example 2C), 50 ml of ethanol and 5.3 g (0.12 mol) of ethylene oxide are in a closed autoclave under Eühren 2 hours at 120 heated to 130 ⁰ C. After the ethanol has been distilled off, 30 g of 50 percent sulfuric acid are added and, after dissolving ^{, the mixture is heated to 80 to 100 °} C. for 5 hours with stirring. After the reaction mixture has been poured into 300 ml of isopropanol, the mixture is stirred while cooling, with Separate crystals. After filtering off and drying the crystals to obtain 19.7 g of 4-amino-3-methyl-N- (ß-hydroxyethyl) -N-ethylaniline sulfate melting at 152 to 154 ⁰ C.

When performing a mixed melting point with an authentic Sample obtained by recrystallizing the commercial product has been made from isopropanol, no melting point depression is observed. The IR absorption spectra of both Products completely match.

Example 5 A. Production of 4-acetamino-3-methyl- (N, N-diethyl) aniline

A mixture of 19.1 g (0.1 mol) of 4-acetamino-.3-meth.yl-N-ethylaniline (obtained in Example 1C) μπα. 100 g of water will 12.5 S diethyl sulfate was added dropwise with stirring. Then the entire reaction system is overnight at

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BATH ORIGINAL

2U8429

Room temperature stirred. After the reaction mixture has been neutralized with sodium hydroxide, the deposited crystals are recrystallized from methanol. 11.5% of white? -; crystalline 4-acetamino-3-diethyl- (N, N-diethyl) aniline of i ^{1 is obtained} . 114 to 115 ⁰ C.

Analysis: C H N,

found: 69.9 9.1 13.1 calc .: 70.87 9.15 12.72

B. Preparation of 4-amino-3-methyl- (N, N-diethyl) aniline hydrochloride

A solution of 22 g of 4-acetamido-3-methyl- (N, N-diethyl) -aniline in 30 g of 50 percent sulfuric acid is heated with stirring for 5 hours at 80 to 100 ⁰ C. After adding 50 g v / water, the reaction mixture is neutralized with 30 percent sodium hydroxide solution and extracted with 150 ml of benzene. After the benzene used has been distilled off from the extract, one obtains

14.4 g of 4-amino-3-methyl- (N, N-diethyl) aniline. For purification, the reaction product is subjected to reduced pressure (13O ⁰ C / 2 torr) of the distillation. Here one obtains

13.5 g of 4-amino-3-methyl- (N, N-diethyl) aniline. The free amine is dissolved in 100 ml of diethyl ether and converted to the hydrochloride by introducing dry hydrogen chloride gas into the system. The salt is then filtered off and dried. In this case, one obtains 17.7 g of 4-amino-3-methyl- (N, N-diethyl) -aniline hydrochloride, mp 261 ⁰ C.

When performing a mixed melting point with an authentic Sample obtained by recrystallizing the corresponding commercial product from isopropanol no melting point depression observed. The IR absorption spectra both products are completely the same.

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BAD ORlGtNAL

Example 6 A. Preparation of 4-phthalimino - ^ - methyl-nitrobenzene

66.6 g (0.45 mol) of phthalic anhydride are added to a Lüsting of 45.6 g (0.3 mol) of 4-amino-3-methyl-nitrobenzene in 250 g of dimethylformamide. The reaction mixture is refluxed for 6 hours and then allowed to cool. Here, 66 g of 4-phthalimiho-3-methyl-nitrobenzene separate from the I ¹ . 195 to

196 ⁰ C •away. found : C. , 5 3, H 9 N Analy se: ber .: 63 , 83 3, VJl 9 , 9 63 57 , 93

B. Preparation of 4-phthalimino-3-methylaniline

An autoclave is charged with 70.5 g (0.25 mol) of 4-phthalimino-3-methylnitrobenzene, 500 ml of tetrahydrofuran and 3 g of freshly made Raney nickel. The autoclave is then pressurized with hydrogen at a pressure of 70 kg / cm. After a reaction time of 3 hours at 80 to 100 ^° C., the Raney nickel is removed and the tetrahydrofuran is distilled off. This gives 53.5 g of yellow crystals from

SV 182 to 182 , 5 ° C. • C. , 0 4th N Analysis: found : 71 , 42 4th 11.8 ber .: 71 11.11 H , 7 , 79

C. Preparation of 4-amino-3-methyl- (N, N-diethyl) aniline hydrochloride

An autoclave is charged with 25 g (0.1 mol) of 4-phthalimino-3-methylaniline, 10 g of water, 31 g of diethyl sulfate and 27 ml of 30 percent sodium hydroxide solution. The reaction mixture is heated in a sealed autoclave for 2 hours at 120 to 13O ⁰ C. To-

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from which the reaction solution has been removed is treated with; 25 g of concentrated sulfuric acid and the reaction mixture is heated to 80 to 100 ° C. for 5 hours while stirring. After the reaction solution has cooled to room temperature, it is neutralized with 30 percent sodium hydroxide solution. The further work-up takes place according to Example ^ B. This gives 15.9 S 4-amino-3-methyl- (N, N-diethyl) -aniline hydrochloride, mp 260 ⁰ C.

When performing a mixed melting point with an authentic Sample which has been prepared by recrystallizing the corresponding commercial product from isopropanol no melting point depression observed. The IB absorption spectra both products are completely the same.

Claims

509820/1 185

Claims (6)

2,48429 patent claims 1. y Process for the preparation of 4-amino-3-methyl-] | -substiiuierten or unsubstituted alkyl anilines, thereby labeled that you can use 4-amino-3-methyl-nitrobenzene of the formula I ■ NO NH, CH, (D with an acylating or sulfonylating agent for the acylation and / or sulfonylation to give a compound of the general Formula II (II) subject, in which E. is a hydrogen atom or an acyl radical, and Ep is an acyl or sulfonyl radical, or E and Rp together represent a divalent acyl radical; the nitro group of the compound of the general formula II with hydrogen in Gegenivart of a Netallhj ^ drierungskatalysators to form a compound of the general formula III 509820/1 185 (III) in which R ^ ₁ and Ep have the aforementioned meaning, the amino group of the compound of the general formula III is reduced with an alkylating agent from the group consisting of alkyl halides, substituted alkyl halides and alkylene oxides of the alkylation to form a compound of the general formula IV (IV) subject, in which IL and Rp have the aforementioned meaning, R ^ denotes an alkyl radical or a substituted alkyl radical, and R _{1 represents} a hydrogen atom, an alkyl radical or a substituted alkyl radical; and the compound of the general formula IV of hydrolysis to form a compound of the general formula V 509 8 20/1 185 CH, (V) subject, in which IU and R ^ have the aforementioned meaning. 2. The method according to claim 1, characterized in that the compound of the general formula V is converted into an inorganic one or converts organic acid salt. 3. The method according to at least one of claims 1 and 2, characterized in that IL is a hydrogen atom, an acetyl or phthaloyl group; Rp represents an acetyl, phthaloyl or p-toluenesulfonyl group; R _{7 is} an ethyl, hydroxyethyl, hydroxypropyl, β-methylsulfonamidoethyl or sulfonylethyl group; and R ^ represents a methyl, ethyl, propyl or hydroxyethyl group. 4. The method according to at least one of claims 1 to "3» characterized in that the acylating agent and / or sulfonylating agent used is a p-toluenesulfonylating agent Phthaloylating agent or an acetylating agent is used. 5. Method according to at least one of claims 1 to 4, characterized in that the hydrolysis agent used is hydrochloric acid or sulfuric acid. 6. The method according to at least one of claims 1 to 5i characterized in that the alkylating agent used is an alkyl halide, a substituted alkyl halide or a Alkvlenoxid used. 509820/1 185