DE1009622B

DE1009622B - Process for the preparation of chlorocyclohexenes and their isomers

Info

Publication number: DE1009622B
Application number: DEE5087A
Authority: DE
Inventors: Alfred Jerome Kolka; Harold David Orloff
Original assignee: Ethyl Corp
Current assignee: Ethyl Corp
Priority date: 1951-03-22
Filing date: 1952-02-21
Publication date: 1957-06-06

Description

Verfahren zur Herstellung von Chlorcyclohexenen und ihren Isomeren Die Erfindung bezieht sich auf die Herstellung von Chlorcyclohexenen und deren Isomeren, insbesondere von Cyclohexenen mit 5 oder 6 Chloratomen, welche die allgemeine Formel besitzen, in der X Wasserstoff oder Chlor bedeutet. Sie können als Produkte einer teilweisen Chloranlagerung an Chlorbenzol betrachtet werden.Process for the preparation of chlorocyclohexenes and their isomers The invention relates to the preparation of chlorocyclohexenes and their isomers, in particular of cyclohexenes having 5 or 6 chlorine atoms, which have the general formula in which X is hydrogen or chlorine. They can be viewed as products of a partial addition of chlorine to chlorobenzene.

Es ist zwar bereits bekannt, durch thermische Behandlung oder mittels Alkalien aus Hexachlorcyclohexan unter Abspaltung von Chlorwasserstoff Pentachlorcyclohexen darzustellen. Although it is already known by thermal treatment or by means of Alkalis from hexachlorocyclohexane with elimination of hydrogen chloride pentachlorocyclohexene to represent.

Die Chlorcyclohexene konnten bisher jedoch nicht nach den bekannten Verfahren durch Chloranlagerung an Chlorbenzol erhalten werden, denn bei allen solchen Verfahren werden 6 Chloratome an den Benzolkern angelagert, und als einziges Reaktionsprodukt wird Heptachlorcyclohexan gebildet. The chlorocyclohexenes, however, have not yet been able to match the known ones Process can be obtained by adding chlorine to chlorobenzene, because with all such Process, 6 chlorine atoms are added to the benzene nucleus, and as the only reaction product heptachlorocyclohexane is formed.

Erfindungsgemäß werden nun Chlorcyclohexene der oben angegebenen Formel durch katalytische Chloranlagerung an ein Chlorbenzol der Formel in der X die oben angegebene Bedeutung besitzt, und durch katalytische Hemmung der Anlagerung nach Aufnahmen von 4 Chloratomen hergestellt, wobei die Chloranlagerung mit überschüssigem Chlor durchgeführt und zweckmäßig durch Bestrahlung mit Licht eingeleitet wird. Als katalytisch wirkender Hemmstoff wird Jod verwendet. Das erfindungsgemäße Verfahren kann ein-und zweistufig durchgeführt werden.According to the invention, chlorocyclohexenes of the formula given above are now obtained by catalytic addition of chlorine to a chlorobenzene of the formula in which X has the meaning given above, and produced by catalytic inhibition of the addition after uptake of 4 chlorine atoms, the chlorine addition being carried out with excess chlorine and suitably initiated by irradiation with light. Iodine is used as a catalytically active inhibitor. The process according to the invention can be carried out in one or two stages.

Die erfindungsgemäß hergestellten Chlorcyclohexene sind allen Umsetzungen zugänglich, die für die Doppelbindung in Olefinen und Vinylhalogeniden kennzeich- nend sind ; sie können als Ausgangsstoffe für Oxydationen, Umsetzungen nach Diels-Alder und bei Reaktionen verwendet werden, bei denen organische oder anorganische Stoffe an die Doppelbindung angelagert werden. Außerdem können die Chlorcyclohexene als Insektizide und Fungizide verwendet werden. The chlorocyclohexenes prepared according to the invention are all reactions accessible, which characterize the double bond in olefins and vinyl halides ending are ; they can be used as starting materials for oxidations, reactions according to Diels-Alder and used in reactions involving organic or inorganic substances are attached to the double bond. In addition, the chlorocyclohexenes can be used as Insecticides and fungicides are used.

Zum besseren Verständnis der Erfindung soll sie an Hand der folgenden Beispiele beschrieben werden, wobei sich alle Teile und Prozentangaben auf Gewichtsmengen beziehen. For a better understanding of the invention, it should be based on the following Examples are described, with all parts and percentages being by weight relate.

Beispiel 1 2,3,4,5,6-Pentachlorcyclohexen- (l) In ein mit Wasserkühlmantel versehenes, senkrecht gelagertes röhrenartiges Reaktionsgefäß aus Glas, das mit einer Einrichtung zur Temperaturmessung, einem Verteilungsrohr für eingeleitetes gasförmiges Chlor und einer Rückflußkühlung versehen und durch eine Infrarotlampe in einem Drittel der Höhe vom Boden des Gefäßes und 25 mm vom äußeren Kühlmantel entfernt beleuchtet war, wurden 2770 Teile Chlorbenzol und 12,5 Teile Jod gegeben. Innerhalb von 5 Stunden wurden 950 Teile Chlor mit einer Geschwindigkeit von etwa 3 Teilen in der Minute eingeleitet und dabei die Temperatur der Reaktionsmischung zwischen 20 und 30° gehalten. Nachdem die Chlorzugabe beendet war, wurde das infrarote Licht abgeschaltet und Stickstoffgas im Dunkeln durch die Reaktionsmischung geleitet, um etwa noch vorhandenes freies Chlor zu entfernen. Dann wurde das Reaktionsgemisch bei einem Druck von etwa 15 mm Quecksilbersäule zur Beseitigung des überschüssigen Chlorbenzols destilliert. Example 1 2,3,4,5,6-pentachlorocyclohexene (l) In one with water cooling jacket provided, vertically stored tubular reaction vessel made of glass, which with a device for temperature measurement, a distribution pipe for discharged gaseous chlorine and a reflux cooling and by an infrared lamp one third of the height from the bottom of the vessel and 25 mm from the outer cooling jacket illuminated remotely, 2770 parts of chlorobenzene and 12.5 parts of iodine were added. Within 5 hours, 950 parts of chlorine were added at a rate of about Initiated 3 parts per minute and the temperature of the reaction mixture between 20 and 30 ° held. After the chlorine addition was finished, the infrared light became switched off and nitrogen gas passed through the reaction mixture in the dark, to remove any free chlorine that may still be present. Then the reaction mixture became at a pressure of about 15 mm of mercury to remove the excess Distilled chlorobenzene.

Der Rückstand wurde mit einer wäßrigen Natriumsuintlösung zur Beseitigung der noch vorhandenen geringen Jodmenge behandelt und dann bei niedrigem Druck fraktioniert destilliert. Bei einem Druck von 5 mm Quecksilbersäule ging bis zu einer Temperatur von 85° eine geringe Menge von Di-und Trichlorbenzolen über. The residue was removed with an aqueous solution of sodium sulphate treated with the small amount of iodine still present and then fractionated at low pressure distilled. At a pressure of 5 mm mercury went up to a temperature from 85 ° a small amount of di- and trichlorobenzenes above.

Dann wurde der Druck auf 1 mm Ouecksilbersäule verringert, und die bis zu einer Temperatur von 110° übergehende Substanz gesammelt. Sie bestand aus 378 Teilen eines Gemisches von Stereoisomeren des 2,3,4,5,6-Pentachlorcyclohexens- (l), entsprechend einer Ausbeute von 21,3 °/0, bezogen auf die in das ReaktionsgefäB eingeleitete Chlormenge. Tetrachlorbenzole wurden während der Destillation nicht abgetrennt. Die Menge der entstandenen Trichlorbenzole betrug etwa 2"/o der eingeleiteten Chlormenge. Der Rest war zur Bildung von Dichlorbenzolen verbraucht worden.Then the pressure was reduced to 1 mm mercury column, and the collected up to a temperature of 110 ° passing substance. It consisted of 378 parts a mixture of stereoisomers of 2,3,4,5,6-pentachlorocyclohexene (l), corresponding to a yield of 21.3%, based on that in the reaction vessel introduced amount of chlorine. Tetrachlorobenzenes were not produced during the distillation severed. The amount of trichlorobenzenes formed was about 2 "/ o that introduced Amount of chlorine. The remainder had been used to form dichlorobenzenes.

Es wurde gefunden, daß 2,3,4,5,6-Pentachlorcyclohexen- (l) eine Mischung von Stereoisomeren ist und daß von solchen Isomeren wenigstens vier zugegen sind. Durch sorgfältige fraktionierte Kristallisation, fraktionierte Destillation und chromatographische Adsorption an Kieselsäure konnten vier Isomere abgetrennt werden, die als a, fol-, y-und b-Isomere bezeichnet wurden. Die physikalischen Eigenschaften und Analysen dieser Isomeren sind folgende : Isomerenart des Schmelzpunkt Siedepunkt 2 3 4 5 6-Pentachlor- cyclohexen- (1) oC oC oo C I o/H o/o Cl index np l I a68, 2bis68, 670, 11 116 bis 118 27,96 1 2, 18 69,82 1,5632 y 58, 2 bis 58, 8 69, 64 b 70, 5 bis 71,3 70, 77 Berechnet für C6H5C16 28, 33 1, 98 69,69 Beispiel 2 1, 2,3,4,5,6-Hexachlorcyclohexen In ein wassergekühltes, senkrecht gelagertes röhrenförmiges Glasreaktionsgefäß, das mit einer Einrichtung zur Temperaturmessung, einem Verteilungsrohr für eingeleitetes gasförmiges Chlor und Rücknußkühlung ausgestattet war und von zwei 250-Watt-Infrarotlampen und zwei 275-Watt-Lampen, bekannt unter dem Handelsnamen vRS-Sunlampsa, in einem Drittel der Gefäßhöhe vom Boden aus gerechnet und 25 mm vom äußeren Kühlmantel entfernt beleuchtet wurde, waren 3110 Teile o-Dichlorbenzol und 9 Teile Jod gegeben worden. Innerhalb von 14,5 Stunden wurden 1000 Teile Chlor mit gleichbleibender Geschwindigkeit eingeleitet und währenddessen die Temperatur des Reaktionsgemisches auf etwa 30° gehalten. Nach Beendigung der Chloreinleitung wurden die Infrarotlampen und, Sunlamps ? abgeschaltet, und Stickstoffgas wurde durch das Reaktionsgemisch im Dunkeln zur Entfernung von nicht umgesetztem Chlor geleitet. Das Reaktionsgemisch wurde dann mit Dampf destilliert und das Destillat in zwei Fraktionen von 2286 und 464 Teilen aufgefangen.It has been found that 2,3,4,5,6-pentachlorocyclohexene (I) is a mixture of stereoisomers and that of such isomers there are at least four present. Careful fractional crystallization, fractional distillation and chromatographic adsorption on silica enabled four isomers to be separated, which were referred to as a, fol, y and b isomers. The physical properties and analyzes of these isomers are as follows: Type of isomer of the melting point boiling point 2 3 4 5 6-pentachloro cyclohexen- (1) oC oC oo CI o / H o / o Cl index np l I a68, 2bis68, 670, 11 116 to 118 27.96 1 2, 18 69.82 1.5632 y 58, 2 to 58, 8 69, 64 b 70.5 to 71.3 70, 77 Calculated for C6H5C16 28, 33 1, 98 69.69 Example 2 1, 2,3,4,5,6-hexachlorocyclohexene In a water-cooled, vertically stored tubular glass reaction vessel, which was equipped with a device for temperature measurement, a distribution pipe for introduced gaseous chlorine and rebut cooling and of two 250-watt infrared lamps and Two 275 watt lamps, known under the trade name vRS-Sunlampsa, were calculated at a third of the height of the vessel from the floor and illuminated 25 mm from the outer cooling jacket, 3110 parts of o-dichlorobenzene and 9 parts of iodine were given. 1000 parts of chlorine were passed in at a constant rate over the course of 14.5 hours and during this time the temperature of the reaction mixture was kept at about 30 °. After the introduction of chlorine, the infrared lamps and, Sunlamps? turned off and nitrogen gas was bubbled through the reaction mixture in the dark to remove unreacted chlorine. The reaction mixture was then steam distilled and the distillate collected in two fractions of 2286 and 464 parts.

Diese bestanden aus Gemischen von Di-und Trichlorbenzolen. Der Destillationsrückstand erstarrte teilweise bei einer Temperatur von 25°. Der gebildete feste Stoff bestand aus 35,5 Teilen 1, 2,4,5-Tetrachlorbenzol, die verbleibende Flüssigkeit war 855 Teile rohes 1, 2,3,4,5,6-Hexachlorcyclohexen. Diese Verbindung kristallisierte bei längerem Stehen ebenfalls und wurde durch Umkristallisieren aus Hexanen gereinigt. Die Ausbeute an Hexachlorcyclohexen betrug 430/ou bezogen auf das verbrauchte Chlor. Das Produkt enthielt 73,7° ; o Chlor, während die auf Grund der Formel C, H, Cl, berechnete Chlormenge 73,65 °/o beträgt. Auch das 1,2,3,4,5,6-Hexachlorcyclohexen ist eine Mischung stereochemischer Isomerer und besteht aus wenigstens zwei Isomeren, die als a-und ß-Isomere bezeichnet werden. Die physikalischen Eigenschaften und die Analysen dieser Isomeren sind folgende : Isomerenart des Schmelzpunkt Analyse 1,2,3,4,5,6-Hexa- chlorcyclohexen C oo Cl a 100 bis 100,5 73,70 1 139, 8 bis 140,4 74,18 Berechnet für C6H4C16 73, 65 Es wurde festgestellt, daß noch andere Isomere in den Gemischen der Chlorcyclohexene vorkommen, wie aus den spektroskopischen Analysen hervorgeht.These consisted of mixtures of di- and trichlorobenzenes. The distillation residue partially solidified at a temperature of 25 °. The solid formed consisted of 35.5 parts of 1,2,4,5-tetrachlorobenzene, the remaining liquid was 855 parts of crude 1,2,3,4,5,6-hexachlorocyclohexene. This compound also crystallized on prolonged standing and was purified by recrystallization from hexanes. The yield of hexachlorocyclohexene was 430 / ou based on the chlorine consumed. The product contained 73.7 °; o Chlorine, while the amount of chlorine calculated on the basis of the formula C, H, Cl is 73.65%. 1,2,3,4,5,6-hexachlorocyclohexene is also a mixture of stereochemical isomers and consists of at least two isomers, which are referred to as α and β isomers. The physical properties and analyzes of these isomers are as follows: Type of isomer of the melting point analysis 1,2,3,4,5,6-hexa- chlorocyclohexene C oo Cl a 100 to 100.5 73.70 1,139.8 to 140.4 74.18 Calculated for C6H4C16 73, 65 It was found that other isomers also occur in the mixtures of the chlorocyclohexenes, as can be seen from the spectroscopic analyzes.

Claims

The usable amount of iodine can be changed within wide limits, z. B. it can be between about 20 and 0.01 parts per 100 parts of chlorine. One The preferred embodiment of the process is to start the addition of chlorine initiate of chlorobenzene or o-dichlorobenzene by exposure to light and they at To interrupt the addition of 2 moles of chlorine per mole of chlorobenzene or dichlorobenzene, by adding one part iodine to 100 parts chlorine. The amount of chlorine used can also be used in relation to the amount of chlorobenzene or o-dichlorobenzene used within further limits fluctuate. It has been found that, surprisingly, the yield of chlorocyclohexene can be increased by continuously adding chlorine in excess introduced into the reaction vessel so that the chlorine does not completely form organic chlorine compounds is implemented. So it becomes an only partially chlorinated addition compound produced by using an excess of chlorine. The temperature range that must be adhered to during the implementation can be chosen arbitrarily, however are in general Temperatures from 70 to + 100 ° are preferable.

The presence of a reactive double bond in the inventive produced chlorocyclohexenes was z. B. by reaction with aqueous potassium permanganate solution proven. For example, the 2,3,4,5,6-pentachlorocyclohexene (l) oxidized to 1, 2-dioxy-3,4,5,6-tetrachlorocyclohexane, if the oxidation at a Temperature of 25 ° was carried out, in contrast to a chlorine-containing dicarboxylic acid with 4 chlorine atoms, if the chlorination takes place at temperatures of 70 to 80 ° had gone.

In this way it could also be determined that only four of the chlorine atoms are bound to methylene carbon atoms of the cyclohexene ring. When treating 1,2,3,4,5,6-hexachlorocyclohexene with alcoholic potassium hydroxide solution there were also only two products, namely 1,2,3,4- and 1,2,3,5-tetrachlorobenzene in roughly equal amounts. The amount of hydrogen chloride released corresponded the theoretically possible amount: C. H, C16-X Cß Ha C14 + 2 H C1.

The method according to the invention also represents a new, immediate way to obtain those tetrachlorobenzenes, which by so far known immediate procedures were not readily available. One obtains z. B. in the chlorination of benzene by substitution mainly the 1,2,4,5-tetrachlorobenzene.

The reactive carbon-carbon double bond in the Chlorocyclohexene is accessible to the normal reactions characteristic of olefins. For example, dibromo derivatives can be prepared by treating the chlorocyclohexenes with bromine can be obtained in an inert solvent. Chlorine reacts in the absence of one Inhibitor, but in the presence of an addition catalyst, with the pentachlorocyclohexene (l) with formation of heptachlorocyclohexane. Strong oxidizing agents can work Hexachlorocyclohexene a tetrachlorodicarboxylic acid can be obtained. Other oxidizing agents too can be used, depending on the nature of these agents either a diol, a dialdehyde or a dicarboxylic acid can arise. Other substances, z. B. butadiene, cyclopentadiene, rhodanic acid, ozone, peracetic acid, cyanogen bromide, Hydrogen cyanide, hydrogen bromide, mercaptans, nitric acid, nitrogen oxides, diazo compounds, Azides, sulfites, arylsulfinic acids and hypohalous acids to the chlorocyclohexenes are accumulated.

Pentachlorocyclohexene (I) which can be prepared according to the invention is included the thermal elimination of hydrogen chloride at higher temperatures, such as 250 to 500 °, or in the presence of alcoholic potassium hydroxide solution, a mixture of trichlorobenzene isomers. It has been found that all possible trichlorobenzene isomers are roughly as follows Quantities arise: 1, 2,4-trichlorobenzene ............... 87 ° / 0 1, 2,3-trichlorobenzene .............. .. 5 ° / 0 1, 3,5-trichlorobenzene .............. 8 ° / 0.

These trichlorobenzenes are also obtained if from the pentachlorocyclohexene (L) hydrogen chloride is split off catalytically. So you can even at one temperature of only 25 ° trichlorobenzenes by treating pentachlorocyclohexene (l) with aluminum chloride obtained in the presence of benzene as a solvent. Of course, this implementation takes place even faster if you higher temperature, e.g. B. with heating and reflux cooling of benzene works. Furthermore, trichlorobenzenes were made from pentachlorocyclohexene (l), z. B. with aluminum chloride, antimony pentachloride and ferric chloride, without application a solvent, obtained at temperatures between 100 and 300 °.

The chlorocyclohexenes which can be prepared according to the invention are both in Effective in the form of mixtures of their steroid isomers as well as in the form of the pure isomers Fungicides. Preventing spores from germinating two species of fungus, namely Alternaria oleracea, and Sclerotinia fructicola, was identified by taking the penta or hexachlorocyclohexene in water in the presence of a dispersant in various concentrations suspended and under the microscope the action of the dispersion on these fungi which were contained in a drop of water on a microscope slide and treated with the dispersions of the chlorocyclohexenes. Under these conditions it was found that ß-pentachlorocyclohexene (l) in concentrations below 100 per million effective and also a-pentachlorocyclohexene (l) was almost as effective. It was also found that under these conditions the hexachlorocyclohexene germination of 50% of the fungal spores if it was in concentrations below 10 per million against Sclerotinia fructicola, and under 100 per million against Alternaria oleracea was applied. The ability to inhibit spore germination of these fungi, is a measure of the effectiveness of such agents in preventing the growth of harmful Mushrooms on major agricultural products.

So is z. B. the fungus Alternaria oleracea is the cause of potato dew, and Sclerotinia fructicola causes harmful fungal growth in peach rot. Other types of fungi that can be controlled by the chlorocyclohexene, and the plant diseases caused by these fungi are shown below Table compiled: Grain diseases: stem rust of wheat ... Puccinia graminis crown rust of oats .... Puccinia coronata Brown spot disease of rice ................... Helminthosporium oryzae oat brandy ............... Ustilago levis Tuber plant diseases : Stalk rot of the sweet potato Fusarium hyperoxysporum Sugar pulp leaf spot disease .............. Cercospora beticola Potato Rhizoctonia disease .................... Rhizoctonia solani fruit disease: apple scab ................ Venturia inaequalis peach rot Erwinia amylovora cherry leaf spot disease Coccomyces hiemalis stem end rot von Citrusfriichten ................ Diaporthe citri It has also been shown that the chlorocyclohexenes which can be prepared according to the invention in all stereoisomers Forms are effective insecticides. You were z. B. in water in the presence of a Dispersant, known under the trade name nTriton X-100rc, suspended.