DE1468241C - Process for the production of halogen derivatives of benzene, naphthalene or diphenyls - Google Patents

Description

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The patent 1468 219 relates to a method according to the invention, for example, the following production of mono-, di- or trichloro or compounds can be produced; Chlorobenzene, bromine mono-, Dj- or tribromo derivatives of benzene, benzene, fluorobenzene, o-, m- and p-dtuuobenzene, toluene, naphthalene, anthracene, diphenyls or p-dichlorobenzene, m-dichlorobenzene, m-dibromobenzene, diphenyl ethers, corresponding mono-, 'S-rn-chlorobromobenzene, p-dibromobenzene, p-Chlordtphe-di- or trisulfonyl chlorides or bromides in counter-nyl, m-bromodiphenyl, 2,4-difluorodiphenyl, 2-Bromwart of chlorinated or brominated aromatic naphthalene, 1,5-dichloronaphthalene.
Hydrocarbons in which at least about the separation of the desired halogensubsti-half of the hydrogen atoms is replaced by chlorine or bromine, aromatic compounds from the product atoms, or by perchlorinated or per- io the thermal decomposition of the aromatic sulfonylbrominated saturated aliphatic hydrocarbons . Halide can normally be effected by any conventional solvent and copper, manganese, or similar process such as cobalt, palladium, platinum or a compound fractional condensation or distillation. ^ Juter these metals as a catalyst at 200 to 300 ⁰ C certain conditions can decompose some of the arothermally. 15 matic sulfonyl halide reproduced unchanged

The present invention now relates to a recovery and, if desired, the cycle

development of the process for the production of the process are fed back.

Halogen derivatives of benzene, naphthalene or Es is from Italian patent specification 390 187

Diphenyls according to patent 1,468,219, whereby one inventively known, aliphatic chlorinated hydrocarbons by

according to the mono- or disulfonyl fluorides, chlorides 20 heating of liquid sulfochlorides aliphatic from the

or bromides of benzene, naphthalene or di-CO hydrogenation of hydrocarbons obtained

phenyls in the presence of palladium, platinum or bodies. In this known method is in the

Copper or an oxide or halide of this liquid phase worked. The boiling point must not

Metals are thermally exceeded at 300 to 400 ⁰ C in the gas phase. To avoid the upper

ZersetzL 35 taking side reactions is recommended,

The inventive method is of particular in the presence of solvents such as toluene or

Value to work on the production of fluorine-substituted aromatic xylene,

table connections. The recommended procedure there leads to

For example, the present case according to the invention cannot lead to success. Furthermore

As is known, fluorobenzene from benzenesulfonyl fluoride causes heating of aromatic compounds

will hold. Sulfonyl halides in the presence of solvent

The replacement of the sulfonyl fluoride group by fluorine means such as toluene or xylene for arylation and

is particularly valuable because the production in no way leads to the formation of the desired halogen

of the lower fluorinated compounds in a pure aromatic compound. This citation

State is not easy by direct methods and 35 could therefore no teaching or teaching to the person skilled in the art

the optional indirect methods, such as diazo replacement, stimulation to dissolve the dissolved according to the invention

give relatively low yields in many cases. Convey the problem.

The method according to the invention is also special. The method according to the invention is carried out by the

valuable for the production of m-Di-halogenverbin- the following examples are explained,

fertilize (halogen = F, Cl, Br) of benzene. 40 _r .

For good results a reaction temperature example must be used

from 300 to 400 ⁰ C, e.g. B. between 325 and 375 ⁰ C, This example describes the production of

be respected. The catalyst must be in a chlorobenzene made from benzenesulfonyl chloride.

Form used which was for the vapor of the benzenesulfonyl chloride in a ratio

Sulfonyl halide is accessible, and in many 45 of 0. Gb5 g / min in a nitrogen stream with a

Cases the catalyst can evaporate on an inert support, flow rate of 25 ccm / min. the

for example charcoal or diatomaceous earth, in powder gases were passed through a misshapen tube, wel-

or in the form of granules. ches had an inner diameter of 1.25 cm

The procedure is usually carried out at atmo * and which contained 10 g of powdered charcoal,

spherical, optionally also with untcralmo- 50 on which 5% palladium, based on the weight

spherical pressure. the charcoal, creating a catalyst

Good results have been achieved by thinning the sator bed 16 cm in length. The vapor of the aromatic sulfonyl halide with U-shaped tube was immersed in a bath which receive an inert gas> for example nitrogen or a Wäirneauslauscherflüssigkelt with eleventh tempera argon before this door comprised of 330 ⁰ C the thermal decomposition 35th

is subject to settlement. For this purpose, for example * The gas flow exiting the U-tube was

1 to 10 volumes of inert gas χ to volume successively by a water-cooled customer

aromatiseriemSulforsylhalogenid vapor, for example salor, through an ice-cooled collecting container and

3 to 5 volumes can be used. passed through a solution of sodium hydroxide. the

In certain cases, the steam of the afema * 60 less volatile constituents were in the be *

table sulfonyl halide is collected with the advantage of the thermal holder, while sulfur dioxide, the main *. * · »

Decomposition in the presence of the corresponding free neuter by-product of the reaction in the sodium s -:

Halogens, so can with the hydroxide solution, was absorbed. Hydrogen chloride, # 3

Production of chlorobenzene or fluorobenzene with ·· a less by-product, was discussed in "> ■

for example, benzenesulfonyl-65 absorbed in the same way. * b

Chlorine or benzenesulfonyl containing chloride vapor * A total of 13.5 g of benzenesulfonyl * "*

Fluoride containing fluoride vapor (and optionally in each * chloride was (during a period of 206 MU ^ *

an inert diluent gas is used in the case of precipitation. grooves) evaporated. Then nitrogen alone became ** <

1

passed through the device for an additional 30 minutes. The liquid that was collected in the collecting container was made with sodium hydroxide solution washed and dried over anhydrous magnesium sulfate, and then 6.0 g of chlorobenzene 5 was obtained (70% yield of benzenesulfonyl chloride) separated therefrom by fractional distillation.

The sodium hydroxide washes were added to the sodium hydroxide solution in which the Mass of sulfur dioxide and hydrogen chloride produced was collected, and the total amount of each gas evolved during the process, was determined by analyzing the solution. It showed an equivalence of 85% for sulfur dioxide and of 9.6% for hydrogen chloride based on benzenesulfonyl chloride.

Example 2

This example describes the preparation of fluorobenzene from benzenesulfonyl fluoride. ^ac

The apparatus and method used to do this were essentially the same like those described in Example 1.

9.2 g of charcoal a; powder containing 5 percent by weight copper (based on the charcoal) was used (this resulted in a catalyst bed 14.5 cm in length), which was maintained at a temperature of 360 "C. A total of 14.4 g of benzol sulfonyl fluoride was used during a Evaporated for 150 minutes in a _{stream of nitrogen at 15 cem / min;} 20% of the evaporated benzene sulfonyl fluoride was recovered as such, and the process produced 2.7 g of fluorobenzene (39% based on unrecovered benzenesulfonyl fluoride), y / elches aq boiling point of from 78 to 8O ⁰ C, had to sulfur dioxide, equivalent to 31% or, 69% to vaporized benzenesulfonyl fluoride.

Claims (2)

Claims; 1. Further development of the process for the preparation of halogen derivatives of benzene, naphthalene or diphenyl according to Patent 1468 219, characterized in that mono- or disulfonyl fluorides, chlorides or bromides of benzene, naphthalene or diphenyl in the presence of palladium, platinum or copper or an oxide or halide of these metals at 300 to 400 ⁰ C in the gas phase thermally decomposed. 2. The method according to claim 1, characterized in that that the vaporous sulfonyl halide used as the starting material is diluted with an inert gas before the thermal decomposition.