HU202488B - Catalytic process for producing chloroformic acid thio esters - Google Patents

Abstract

The present invention relates to a catalytic process for the chloroacetic acid thioesters of the formula (I) wherein R 1 is C 1-10 straight or branched alkyl, C 2-6 alkenyl, C 5 -C 7 cycloalkyl, benzyl, benzyl; naphthyl, or phenyl optionally monosubstituted by halogen, by reaction of the corresponding mercaptan derivative and phosgene, such that the reaction is carried out at a temperature of 0-150 ° C and a phosphorus compound (Π) and / or (ΙΠ) or (TV). (s) used alone or together with N, N-di- (C 1 -C 4) alkylformamide or tetra- (C 1 -C 5) alkyl urea. In the formulas of phosphorus-containing compounds, X is two or three identical to or different from oxygen or sulfur, Y 1, Y 2 and Y 3, and is defined as halogen, -R 2, NR 3 R 4, -OR 5, or -SR 5 wherein R 2 is C 1-10 alkyl. or phenyl, R3 and R4 are the same and are C1-C5 alkyl, or R3 and R4 taken together with the nitrogen atom are morpholino, piperazino, imidazolyl or piperidino, R5 is C1-C7 alkyl. R, -5 ~ C0C (Figure I) v, -Pv, γ (II) to Yj ~~ P Ya (ΙΠ) Ya Scope of the description: 8 pages (including Figure 4) Ci p®_Y3 Ya Ci (TV ) Figure 20

Description

FIELD OF THE INVENTION The present invention relates to a catalytic process for thioesters of chloroformate of formula (I) wherein R 1 is straight-chain or branched C 1 -C 10 alkyl, C 2 -C 6 alkenyl, C 5 -C 7 cycloalkyl, benzyl, naphthyl, or in the case of a halogen monosubstituted phenyl group, by reaction of the corresponding mercaptan derivative with phosgene by reaction at a temperature of 0-150 ° C and the catalyst (s) having the formula (Π) and / or (ΙΠ) or (IV) as catalyst used alone or in combination with N, N-di- (C 1-4) alkylformamide or tetra- (C 1-5) alkylurea. In the formulas above

X is oxygen or sulfur,

Two or three of Y1, Y2 and Y3 are the same or different and each represents halogen, -R2, -NR3R4, -OR5, or -SR5, wherein

R 2 is C 1 -C 10 alkyl or phenyl, R 3 and R 4 are the same and are C 1 -C 5 alkyl, or R 3 and R 4 taken together with the nitrogen atom are morpholino, piperazino, imidazolyl or piperidino, R 5 is C 1 -C 7 alkyl.

In the last decades, thiocarbamate-type herbicides have been widely used in chemical plant protection, the reaction of which is carried out by reaction of secondary amines with alkylthioesters of formic acid.

Chloroformic acid alkyl thioesters are therefore of particular importance and the processes for their preparation are the subject of several patents. These processes are essentially S-acylation reactions between phosgene and the appropriately substituted mercaptan derivative. The simplest laboratory method is that mercaptan is saturated with phosgene at 0 ° C and allowed to stand until hydrochloric acid is complete. [B. Sturm and G. Gattow Z. anorg. barely. Chem., 508, 136 (1984)]. Thus, ethyl thioester of chloroformate and n-propyl thioester of formic acid were obtained in 65-75% yield.

Benzene as solvent, sodium hydroxide solution as acid acceptor [H. Tilles, J. Am. Chem. Soc., 81714 (1959)], n-propylthioester of formic acid and tertiary (2-chloroethyl) -thioester of formic acid 60 and 60, respectively. It was produced in 55% yield.

Also in a benzene medium, but using a pyridine acid acceptor, the tert-butylthio ester of chloroformate and the tertiary amylthioester of formic acid were respectively 75%. 65% yield.

[R. L. Stanley and D.S., T. J. Org. Chem., 42, 3686 (1977). Various catalysts have been used to accelerate the slow reaction of mercaptan-phosgene. For example, aluminum chloride. [J. Kollonits et al., Chem. Bér. 89, 2293 (1956)], 70, ill. A yield of 45% was obtained for the preparation of tert-butyl thioester of chloroformate and benzyl thioester of chloroformate.

Activated carbon was the most commonly used catalyst in the industry. (e.g., U.S. Patent Nos. 3,093,537,3,165,544 and 4,012,405, U.S. Patent Nos. 2,652,959, 2,721,683, and 2,809,776).

In U.S. Patent Nos. 3,093,537 and 3,165,544, the reaction is carried out with a high excess of phosgene, however, the yield of alkyl mercaptan is only 70-75% and the thioester content of the crude product is about 90%.

According to German Patent Publication No. 2,652,959, the conversion rate of alkyl mercaptan is improved by reacting phosgene and alkyl mercaptan in two series connected tank reactors, DC and liquid phase. Thus, an alkyl thioester of chloroformate containing up to 2% of disulfide impurities is recovered, while the conversion rate of alkyl mercaptan is improved to about 90%.

U.S. Pat. No. 4,012,405 discloses a tubular reactor continuous operation system wherein the first reactor is tubular and activated carbon is contained in the tubing. The second reactor contains an activated carbon bed. Both are operated as riser reactors

By this method, a conversion of 94% was achieved and a 98% purity ethyl chlorothionate of formic acid was prepared. Similarly, the process disclosed in US Patent No. 2,721,683, utilizes two tubular reactors to improve the conversion of alkyl mercaptan by coupling even a gas separation column to the system and purging the crude reaction mixture with hydrogen chloride gas and excess phosgene. There is thus obtained 97.5% yield of chloroformic acid octyl thioester and 99% yield of chloroformate butyl thioester.

Instead of heterogeneous catalysis of activated carbon, homogeneous phase catalysts have been developed in recent years, a common feature of which is that all nitrogenous organic compounds are present.

U.S. Pat. No. 3,277,143 Phosgenates ethyl mercaptan in the presence of substituted acid amides to give ethyl thioester of chloroformate in 79% yield.

U.S. Pat. No. 3,299,114 provides tertiary amines, pyridine, quinoline and pyrrole derivatives to produce aliphatic and aromatic chloroformate thioethers in a yield of up to 89%.

In the process described in German Patent Publication No. 2,212,766, ethyl mercaptan and phosgene are reacted in two steps using triethylamine as acid acceptor in the presence of a thiocarbamate catalyst. The thiocarbamate and a portion of the final product are recycled during the process to give the 95% active ingredient ethyl chlorothioate.

No. 2,934,657 discloses the use of dimethylformamide, tetramethylurea and N-methylpyrrolidone catalysts for the preparation of aromatic and aliphatic chloroformate thioesters. The purity of the obtained products is between 97-99% and the yield about 98%

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US-A-3 025 654 and US-A-4 320 070 disclose the preparation of chloroformic acid thioester with secondary amine, quaternary ammonium salt and basic ion exchange resin catalysts to yield 9095% pure products. EP-A-53981 discloses the use of symmetrically or asymmetrically substituted alkyl ureas and thioureas in the presence of 97-99% yield and 97-98% active ingredient. This patent application describes the preparation of urea derivatives from urea derivatives as phosgene and as catalysts. use.

The disadvantages of the known processes for the preparation of the chlorothionic acid thio-ester can be summarized as follows. Without the use of a catalyst, the reaction may be slow and may take several days. Using NaOH as an acid scavenger, the yield is low due to ester degradation and dialkyl dithiocarbonate formation. The use of the aluminum chloride catalyst is difficult and the dewatering difficult, the process is only a laboratory method.

The disadvantage of the heterogeneous catalysis methods using activated carbon is that the process at the interface has a lower selectivity and more by-products are produced than the processes using homogeneous catalysis.

In a reactor filled with activated carbon, the flow of material is uneven and there is a risk of channel formation or blockage of the reactor. Temperature control of packed tube reactors is cumbersome, temperature distribution is not uniform, local overheating occurs, and this is mainly the reason for the formation of by-products

The reaction rate is still relatively low, requiring the use of a multi-tube reactor system, product feed, post-product purification, and possibly reacting under pressure. Adjusting and maintaining the temperature accurately requires a complex system, the low reaction rate requires a large volume of equipment and the recycling of materials. Due to the gradual inactivation of the catalytic converter, the system parameters are not stable during operation and must be corrected gradually. Frequent replacement of exhausted catalysts is difficult, polluting the environment and not regenerated. The resulting product can only be purified by distillation from unmodified starting material and by-products formed. Undistilled products are dark in color and can only rarely achieve yields and drug contents greater than 95% in practice.

Therefore, activated carbon catalysis can generally only be carried out in very low conversion for the production of higher carbon atoms suitable for the preparation of ethyl thioester of chloroformate.

Nitrogen-containing catalysts have the advantage over the activated carbon process of the possibility of homogeneous catalysis, but have the disadvantage that the catalysts used not only promote the formation of the chloroformate thioesters, but also their decomposition, especially at elevated temperatures. As a result, distillation can only be performed with a low yield and a high loss. This is a particular problem especially for higher boiling thioesters.

Nitrogen-containing catalysts exert their beneficial effects over a relatively narrow temperature range. At a lower temperature, no significant increase in the reaction rate has yet occurred, but the use of a higher temperature results in damage to the alkyl thioester. These catalysts are also suitable for only a few cycles, after which they are deactivated and by-products that inhibit the operation of the equipment are formed.

The object of the present invention was to obtain chloro-formic acid thioesters by homogeneous phase catalysis, in good yield, with sufficient reaction rate, to obtain a stable, high purity final product.

It has been found in our research that these objectives are achieved when the phosphorus-containing compounds of formula (Π) and / or (D1) or (IV) alone or N are used as catalysts for the reaction of phosgene and mercaptan; Together with N-di (C1-C4) -alkylformamide or tetra (C1-C5) -alkyl urea. In the formulas, X is oxygen or sulfur

Two or three of Y ₁ Y 2 and Y ₃ are the same or different and represent a halogen atom, -R 2, NR.SR 4, -OR 5 or -SR 5, wherein

R2 is C1-C10 alkyl or phenyl,

R ₃ and R 4 are the same and are 1-5 acenyl alkyl or

R ₃ and R 4 together with the nitrogen atom are morpholino, piperazino, imidazolyl, or piperidino,

R5 is C1-C7 alkyl.

Examining the structure and mechanism of action of the phosphorus-containing catalysts, the following were found.

The catalysts of formula (Π) with phosgene are of the following structure: PYiY ₂ Y ₃ + coci ₂ - [Y ₁ Y ₂ Y ₃ P®-coci]

The compound thus formed reacts much faster with mercaptan than phosgene itself, so the catalysts of formula (Π) accelerate the reaction by increasing the activity of phosgene:

[YiY ₂ Y ₃ P © COC1] C1 © + Ri-SH PYl Y ₂ Y ₃ + R 1 -S-COQ + HCL (Π) (I)

The catalysts of formula (JU) are soluble in mercaptan or dissolved in phosgene upon conversion to a catalyst of structure (TV) through a complex of unstable structure with loss of carbon dioxide:

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Y1Y2Y3PO + COC1 ₂ - * [YiY2Y3P ⁺ O-COC1] CL - »[YiY2Y3P ⁺ a] a-co2 (ni) - (IV)

Compounds of formula (ΙΠ) can be prepared from phosgenation of compounds of formula (IV) in a solvent medium, such as dichloromethane, outside the thioester-forming reaction, and the compound of formula (IV) thus externally administered also accelerates the thio reaction with mercaptan. ester formation as if the compound of formula (ΙΠ) was introduced into and formed from the reaction. Mercaptan reacts with the phosphonium salt of formula IV to produce the following compound:

[Y1Y2Y3P ^{+ drive} - + R! -sh (IV) [YlY ₂ Y3P ⁺ SRi] Cl- + HCl which is converted to the phosphonium salt of formula (TV) by the action of phosgene to form the chloroformate thioester of formula (I) * [YlY ₂ Y3P ⁺ SRi] Cl- + COCI2- * [Y1Y2Y3P ⁺ ay - + Ri-s-coci (arc) (i)

In fact, the phosphonium salt of formula IV activates mercaptan because the resulting mercaptophosphonium compound is capable of reacting faster with phosgene than mercaptan itself.

By examining the structure of the catalysts of formula (IV) in more detail, a relationship was found between increasing the reaction rate and the structure. When Y1, Y2, and Y3 are all the same and NR3R4, the strongest catalytic effect was observed. These triamide-type phosphonium salts have the following interfaces and the like. characterized by mesomeric structure *

Substitution of -NR 3 R 4 groups with -OR 5 -SR 5 groups or halogen atoms reduces the reaction time less than in the absence of catalyst. The reason is that the symmetric mesomeric structure is -OR5. halogen atom, it may be less stabilized because the oxygen or due to the higher electronegativity of the halogen atoms, the electron-doping nature is suppressed.

The efficiency of the catalyst decreases in a logenic order-NR3R4> -OR5> ha10.

In summary, the catalysts of formula (Π) accelerate the reaction by increasing the reactivity of phosgene, the catalysts of formulas (H1) and (IV), either in or outside the system. In some cases (e.g., when one or more of the halogen atoms in Y1, Y2, Y3) are present, the catalyst may react with the mercaptan to be converted. In this case, of course, the reaction product exerts a catalytic effect. The listed phosphorus-containing catalysts are useful in the preparation of chloro formic acid thioesters of formula (I) wherein R 1 is C 1-10 straight or branched alkyl, C 26 alkenyl, C 5-7 cycloalkyl, benzyl, naphthyl or phenyl optionally monosubstituted with halogen.

Further experiments have shown that the organic phosphorus compounds of formula (Π), (ED) and (TV) are used in combination with N, N-di (C 1 -C 4) -alkylformamide or tetra (C 1 -C 5) ) -alkyl urea eliminates the disadvantages of nitrogen-containing catalysts. Product stability is increased, at higher temperatures and higher reaction rates in the absence of alkylthioester than phosphorus compounds.

One special case of mixed catalysis is the use of the so-called Vilsmeier-Haack complex. These compounds are formed, for example, from N-methyl formanilide or dimethylformamide by the action of phosphorus oxychloride:

Z-N-C * I

CH _a

· WCtj

1®

POjClj © α h c

H

Ζ ^{/ Η} \ η ₃

wherein Z is alkyl or aryl.

In this case, not only is it a simple mixture catalysis, but the catalysts react with each other and the complex structure of the mercaptan activator will be different.

Vilsmeier-Haack-type complexes, which may also be used individually and formed under reaction conditions, react with mercaptan as follows:

Γα η Ί • THE* \ z s κ>, α, ® · «, - 5ΐι - V 1 Ach, z> 1 CH

POjCIj® »HCl

EN 202 488 Β then the phosgone, while the thioester is formed:

z-NI

CH?

C * * POCl ₃ ^X H α h \ /

POjClj® z * x Z CHj

The Vilsmeier-Haack complex thus recovered reacts with another molecule of mercaptan to carry on the reaction.

The advantages of using the phosphorus-containing catalysts of the present invention can be summarized as follows:

1. Homogeneous phase catalysis, thus disadvantages of heterogeneous phase catalysis (limited heat and material transfer)

2. At the end of the reaction, the catalyst precipitates out of the reaction mixture and forms a filterable precipitate, particularly in the case of phosphorus triamides.

3. The filtered catalyst does not lose its activity and can be recycled.

4. The thioester formed is stable and does not decompose at higher temperatures.

5. The resulting thioester can be further purified by distillation without decomposition.

6. The catalyst inhibits the formation of dialkyl disulfide. Only the disulfide content of the starting material can be detected in the product.

7. The formation of dialkyl dithiocarbonate is also relatively lower using the catalyst.

8. High conversion due to the use of catalyst. In the product max. 0.1% of starting material remains.

9. Reaction rates can be significantly increased by up to 40-50% for some catalysts, such as hexamethylene phosphoric triamide, resulting in a similar reduction in reaction time.

10. Since one of the two side reactions (disulfide formation) is virtually eliminated and the other (dithiocarbonate formation) is greatly suppressed, the conversion is high, the resulting end product is highly pure, depending on the purity of the starting material.

11. For these reasons, the yield is 98-99%.

12. Since the catalyst does not decompose the product, the thioester is stable and colorless.

13. The stable thioester can be phosgene and hydrochloric acid depleted at higher temperatures and degassing can be accomplished in less than 10 days using less inert gas.

14. The presence of iron or other inorganic metal salts does not affect the purity, yield, color or stability.

15. The reaction may be carried out in either batch or continuous mode.

16. It does not require the use of separate solvents, so the associated disadvantages (separation, regeneration, loss of material, etc.) can be avoided.

The catalytic process of the present invention is illustrated by the following examples, which are not to be construed as limiting the scope of protection.

1-67. examples

Into a flask equipped with a stirrer, a condenser, a glass inlet funnel, a thermometer, 1 mole of mercaptan RiSH and 0.211.4 g of catalyst were introduced and 1.56 moles of phosgene gas were introduced at the temperature indicated in Table 1. After the phosgene administration is completed, approx. After 1015 minutes post-mixing, the unreacted phosgene and the resulting hydrochloric acid were blown out with dry nitrogen at a temperature between 40-80 ° C.

The names of the mercaptan derivatives used in the reactions, (Π) and (.), Respectively. The catalysts of formula (ΙΠ) and amounts, the temperature employed, the yield (calculated as Ri-SH) for each reaction, and the purity (determined by gas chromatography) of the thioesters formed are shown in Table I.

Table I

Example Mercaptan- Catalyst How much- of g temperatures being C thioester Cleanliness % Kiterme- Meeting % row- number derivative i Rí X Yi Y2 Y3 First Second Third 4th 5th 6th 7th 8th 9th 10th First ethyl SHE N (Me) ₂ N (Me) 2 N (Me) 2 0.5 30 98.5 98.1 Second 1-Propyl SHE N (Me) ₂ N (Me) 2 N (Me) 2 0.6 55-60 96.8 96.8 Third 2-propyl SHE N (Et) 2 N (Et) 2 N (Et) ₂ 0.6 45-50 96.5 97.0 4th 1-butyl SHE N (Me) ₂ N (Me N (Me) ₂ 0.7 65-70 97.3 96.9 5th 2-butyl SHE N (E02 N (Et) 2 N (Et) ₂ 0.7 60-65 97.1 973 6th iso-butyl SHE N (Et) ₂ N (Et) ₂ N (Et) ₂ 0.7 60-65 96.5 97.0 7th tert-butyl SHE N (Et) ₂ N (Et) ₂ N (Et) ₂ 0.7 40-45 94.3 963 8th 1-pentyl SHE N (Pr) ₂ N (Pr) ₂ N (Pt) ₂ 0.8 80-85 98.1 98.3 9th 2-Me-1-butyl SHE N (Pr) 2 N (Pr) _Z N (Pr) 2 0.8 80-85 98.2 98.0 10th 1-Me-1-butyl SHE N (Pr) 2 N (Pt) ₂ N (P) 2 0.8 80-85 98.1 98.4

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Example Mercaptan- X Catalyst Y3 How much- of g temperatures being 'C thioester Cleanliness % Kiterme- Meeting % row- number derivatives Ri YI Y2 First Second Third 4th 5th 6th 7th 8th 9th 10th 11th 1-octyl SHE N (Me) ₂ N (Me) ₂ N (Me) 2 0.8 50 96.2 98.1 12th 1-octyl SHE N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.8 60 97.3 98.0 13th 1-octyl SHE N (Me) ₂ N (Me) ₂ N (Me) 2 1.4 70 98.5 98.2 14th 1-octyl SHE N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.8 80 99.4 98.2 15th 1-octyl SHE N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.8 90 98.3 98-0 16th 1-octyl SHE N (Me) 2 N (Me) ₂ N (Me) ₂ 0.8 100 97.4 97.5 17th 1-octyl SHE N (Et) ₂ N (Et) ₂ N (Et) ₂ 0.8 80 99.0 98.0 18th 1-octyl SHE N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.5 + 80 98.8 98.0 SHE N (Pr) 2 N (Pr) ₂ N (Pt) ₂ 0.5 19th phenyl SHE N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.6 80 99 98.1 20th phenyl 0 N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.6 120 96.2 97.4 21st benzyl 0 N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.8 50 95.8 96.0 22nd 4-Cl-phenyl She N (Me) ₂ N (Me) 2 N (Me) 2 1.2 120-130 95.7 96.4 23rd 2-naphthyl 0 N (Me) ₂ N (Me) ₂ N (Me) ₂ 1.4 120-130 95.0 95.2 24th allyl 0 N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.2 40 95.0 95.8 25th cyclohexyl 0 N (Me) ₂ N (Me) ₂ N (Me) ₂ 0.9 100 95.1 96.0 26th octyl 0 octyl octyl octyl 0.8 90 95.0 97.9 27th octyl 0 phenyl phenyl phenyl 0.8 90 93.2 95.4 28th octyl 0 ethyl ethyl phenyl 0.8 90 94.5 95.8 29th octyl s phenyl phenyl phenyl 0.8 90 92.4 93.2 30th octyl 0 the the the 0.8 90 94.3 97.0 31st octyl 0 the cl propyl 0.8 90 94.0 96.5 32nd octyl 0 the propyl propyl 0.8 90 94.1 95.1 33rd octyl s the the propyl 0.8 90 93.5 95.2 34th octyl - phenyl phenyl phenyl 0.8 90 92.1 95.3 35th octyl - the the the 0.8 90 93.4 95.6 36th octyl - the propyl propyl 0.8 90 93.5 94.1 37th octyl - Br Br Br 0.8 90 94.5 93.8 38th octyl 0 Br propyl propyl 0.8 90 94.2 95.3 39th butyl 0 EtO EtO EtO 0.7 65-70 95.4 96.1 40th butyl s EtO EtO EtO 0.7 65-70 93.2 94.0 41st butyl - EtO EtO EtO 0.7 65-70 92.4 94.1 42nd butyl 0 Sad Sad Sad 0.7 65-70 93.1 95.9 43rd butyl 0 Sad Sad Sad 0.7 65-70 92.2 95.1 44th butyl - Sad Sad Sad 0.7 65-70 90.7 95.3 45th butyl 0 EtO EtO Sad 0.7 65-70 92.1 94.4 46th butyl - EtO Sad Sad 0.7 65-70 91.3 92.6 47th butyl 0 EtO EtO N (PR) 2 0.7 65-70 95.1 95.8 48th butyl 0 EtO N (PR) ₂ N (PR) 2 0.7 65-70 95.8 96.0 49th butyl 0 cyclopentyl N (PR) ₂ N (PR) ₂ 0.7 65-70 95.0 96.0 50th octyl 0 EtO EtO the 1.0 90 93.4 93.1 51st octyl 0 EtO cyclopentyl the 1.0 90 93.0 92.7 52nd octyl 0 phenyl EtO N (PR) ₂ 1.0 90 94.4 92.5 53rd octyl 0 phenyl EtO N (PR) 2 1.0 90 94.3 92.7 54th octyl s phenyl phenyl N (PR) ₂ 1.0 90 94.1 93.7 55th octyl s EtO EtO N (PR) ₂ 1.0 90 92.2 94.1 56th octyl - EtO EtO N (PR) 2 1.0 90 90.1 94.8 57th octyl - the N (PR) 2 N (PR) 2 1.0 90 94.1 93.7 58th octyl - the the Sad 1.0 90 91.3 94.1 59th octyl - N (Bu) ₂ N (Bu) ₂ N (Bu) 2 1.0 90 94.5 93.9

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Example Number of mercaptan series derivative Rj X Yi Catalyst Y2 Y3 How much- Temperature g ° c thioester Cleanliness % Kiterme- Meeting % First Second Third 4th 5th 6th 7th 8th 9th 10th 60th octyl 0 1.0 90 93.4 93.5 61st octyl 0 1.0 90 92.1 93.2 62nd octyl She 1.0 90 92.3 93.0 63rd octyl - 1.0 90 93.8 92.9 64th octyl - 1.0 90 92.7 93.1 65th octyl - 1.0 90 93.1 92.7 66th octyl 0 1.0 90 95.4 95.5 67th octyl - 1.0 90 94.8 93.9

68-72. examples

The procedure of Example 18 was repeated using two catalysts (O) and one catalyst (H) in a total amount of 0.8-1.2 g. The names of the mercaptan derivatives, the catalysts and their amounts, the temperature employed, the yield (calculated as R 1 -SH) for each reaction and the purity of the thioesters formed (determined by gas chromatography) are shown in Table Π. are summarized in Table.

Π. spreadsheet

Example Mercaptan- Catalyst Y2 Y3 How much- of g temperatures being • c thioester Cleanliness % Kiterme- Meeting % row- number derivatives Ltd. X Yi 68th 1-octyl 0 N (Et) 2 N (Et) 2 N (Et) 2 0.4 80 98/7 98.1 - N (Eth N (Et) ₂ N (Et) ₂ 0.4 69th 1-octyl 0 N (Pr) ₂ N (Pr) ₂ N (Pr) ₂ 0.5 80 98.0 98.2 - N (Me) 2 N (Me) 2 N (Me) 2 0.5 70th 1-octyl 0 Sample check Sample check Sample check 0.5 80 99.2 98.1 - Sample check Sample check Sample check 0.5 71st phenyl 0 N (Me) ₂ MeO N (Me) 2 Sample check N (Me) ₂ MeO 0.5 0.5 120 98.4 98.0 72: 4-Cl-phenyl 0 EtO N (Me) 2 EtO N (Me) 2 EtO N (Me) ₂ 0.6 0.6 120-130 98.2 97.0

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Example 73

200 ml abs. dissolved in dichloromethane, 17.9 g / 0.1 mol. (hexamethylphosphoric triamide [JH] catalyst) was cooled to 0 ° C and 14.85 g (0.15 mol) of phosgene gas was introduced into the solution with stirring. The temperature was maintained at 0 ° C A white precipitate formed which was filtered off with excess phosgene and liberated 1 g (IV). as a catalyst for the preparation of the octylthio thioester of chloroformate as described in Example 15. 10

The thus obtained octylthioester had a purity of 98.1% and a yield of 97.9%.

Example 74

The procedure described in Example 15 was followed except that the catalyst was 1: 1 gold (0.5 g + 0.5 g) in dimethylformamide and hexamethylphosphoric triamide (catalyst [ΙΠ]). used

The purity of the octylthioester is 97.25% and the yield is 97.5%. 20

Example 75

The procedure described in Example 15 was followed except that the catalyst was a 1: 1 mixture of tetraethylurea and hexaethylphosphoric triamide ([ΙΠ]) (0.5 g + 0.5 g). )

The purity of the octylthioester was 96.9% and the yield was 96.0%.

Example 76 30

The procedure described in Example 15 was followed except that a 1: 1 mixture of POCL3 (catalyst [ΠΙ]) and dimethylformamide (0.5 g + 0.5 g) was used as the catalyst.

The purity of the octylthioester is 94.4% and the yield is 35 953%.

Example 77

The procedure described in Example 15 was followed, except that 1 g of the separately prepared Vilsmeier-Haack complex (POCL3 + dimethylformamide adduct) was used as the catalyst.

The purity of the octylthioester is 94.2% and the yield is 95.5%.

Claims (1)

Catalytic process for the chloroformic acid thioesters of formula (I) wherein R 1 is straight or branched chain alkyl, C 1-6 alkenyl, C 5-7 cycloalkyl, benzyl, methyl or optionally mono-substituted phenyl - reacting the corresponding mercaptan derivative with phosgene, characterized in that the reaction is carried out at a temperature of 0 to 150 ° C, using as catalysts the phosphorus-containing compound (II) and / or (ΙΠ) or (TV) Together with N-, N-di (C1-C4) -alkylformamide or tetra- (C1-C5) -alkylurea in the above formulas X is oxygen or sulfur, Two or three of Y ₁ , Y ₂ and Y ₃ are the same or different and represent a halogen atom, -R ₂ , NR ₃ R 4, -OR 5 or -SR 5, wherein R ₂ is C 1 -C 10 alkyl or phenyl, R3 and R4 are the same and are C1 -C5 alkyl, or R3 and R4 taken together with the nitrogen atom are morpholino, piperazino, imidazolyl or piperidino, R5 is C1-C7 alkyl. d ς mrc