DD143424A5 - PROCESS FOR THE PREPARATION OF 1,1,1,3-TETRAHALO-4-METHYLPENTANE - Google Patents

Description

212565

Process for the preparation of 1,1,1 _r 3-tetrahalo-4-methylpentane

Field of application of the invention

The present invention relates to a novel process for the preparation of 1,1,1,3-tetrahalo-4-methylpentane. "

"Characteristic of the known technical solutions

1 »1» 1 »3-Tetrahalo-4-methylpentane prepared in accordance with the present invention is a valuable intermediate in the preparation of synthetic pyrethroid esters.

Synthetic pyrethroid esters structurally similar to natural pyrethrin are well known as insecticides of high stability and low toxicity with respect to mammals. These synthetic esters are superior to the naturally occurring pyrethrins in various fields. The naturally occurring pyrethrins decompose rapidly and the insect-killing effect is rapidly neutralized by air and light. "Furthermore, the naturally occurring compounds are not abundantly available and the extraction of this natural compound is very costly.

-Z- 12.3.1979

Divisional application AP CO7C / 2O1, 55 122/12

On the contrary, gene have a higher stability. The ability to decompose, however, is still such that there are no problems for the environment. Also, the synthetic pyrethroid esters are resistant to oxidation by light. Additionally, the pyrethroids have low toxicity with respect to mammals and humans as compared to other insecticides, and yet are highly potent with respect to a large number of insect species.

For the 1,1,1,3-tetrahalo ~ 4-methylpentane a number of manufacturing processes are known, but also have disadvantages. Thus, in most known processes, the yield is too low.

Aim of the invention

The aim of the invention is to propose a method which can be carried out with high yield.

Explanation of the essence of the invention

The present invention relates to a process for producing 1,1,1-tetrahalo-methylpentane by the addition reaction of a tetrahalomethane with 3-methyl-1-butene. If the four halogen atoms in the prepared pentane are to be identical, the halogen atoms in the tetrahalomethane must also be identical. "Carbon tetrachloride is preferably used as the tetrahalomethane. The reaction can also be carried out with a tetrahalomethane in which two different halogen atoms are present. Examples of such compounds are e.g. CCI-Br

-21 2 5 65 - ³ "12.3.1979

Ausseheidungsanmeldung

AP C07C / 20X 55 122/12

and CFpBr ₂ . In the former case, 1,1,1-trichloro-3-bromo-4-methylpentane is obtained as the substituted pentane. In the latter case, 1,1-dichloro-1,3-difluoro-4-methylpentane is obtained. Both pentanes thus obtained can be used to carry out the cracking reaction of the present invention. To carry out the above-described addition reaction, a number of catalysts are known. As examples of such catalysts may be listed: copper chloride, cuprous chloride, ferric chloride, ferrous chloride, ferrous chloride with benzoin, ruthenium (II) -triphenylphosphine complexes, organic peroxides, and cobalt-II salts. Examples of ruthenium-II-triphenylphosphine complexes are dichlorotris (triphenylphosphine) ruthenium (II) and dichlorotetrakis (triphenylphosphine) ruthenium-II.

Organic peroxides (including hydrogen peroxide) have the following general formula; ROOR ¹ , in which R and R ^{1 represent} hydrogen or organic radicals. Such peroxides include hydroperoxides in which R is hydrogen and R ^{1 is} alkyl, cycloalkyl, cycloalkenyl, alkaryl, aralkyl and heterocyclic radicals up to 12 carbon atoms; the dialkyl peroxides in which both R and R 'represent an alkyl group of up to 12 carbon atoms? Diaralyl peroxides in which R and R ¹ each represent an aralkyl group having up to 20 carbon atoms; aliphatic peroxyacid in which R is hydrogen and R * is alkanoyl or aroyl of up to 12 carbon atoms; peroxyesters of said peroxyacid in which R is an alkyl or aryl of up to 12 carbon atoms;

-4- · 12.3.1979

Divisional application AP CO7C / 20J, 110 55 122/12

R ^{1 represents} an alkanoyl or aroyl having up to 12 carbon atoms; Diacycperoxyde in which R and R 'each represent an alkanoyl group having up to 12 carbon atoms? Diaroyl peroxides in which R and R 'each represent an aroyl group having up to 12 carbon atoms and dialkyl peroxydicarbonates, 1-hydroxyalkyl hydroperoxides, bis (1-hydroxyalkyl) peroxides, polyalkylidene peroxides, alkyl-1-hydroalkylperoxides and peroxyacetals.

Preferred organic peroxides used are those in which R and R ^{1 are} hydrogen, alkyl having 1 to 4 carbon atoms, aralkyl having up to 12 carbon atoms, alkanoyl having up to 12 carbon atoms or aroyl having up to 12 carbon atoms.

To carry out the reaction may be any cobalt II ~ _s salts which are soluble in the tetrahalomethane used. Such salts include ζ. Β. Cobalt II hexamino naphthalene β-sulfonate, cobalt II hexamine picrate, and the various cobalt II alkylated naphthalene sulfonates, e.g. For example, cobalt-II-methyl-naphthalene sulfonate and cobalt-II-ethyl-naphthalensulfonat.

For a better understanding of the invention, reference is made to the following example.

Ausfüh approximately example

Into a 340 g reactor the following compounds were introduced:

2125 65 -5- 12.3.1979

Registration application AP-GVIG / 20% 55 122/12

175 ml (1.75 moles of ₄

0.2002 g dichlorotris (triphenyl-

phosphine) ruthenium - II

105 g (1.5 mol) of 3-methylbutene

The air in the reactor was removed and the reactor was placed in a bath at 75 ^° C. and stirred for 20 hours. The reactor and contents were then cooled and unreacted CCl and 3-methylbutene were removed by distillation. There were 286 g (yield 85 %) 1,1,1,3-tetrachloro-4-methylpentane at 96% purity unit.

Claims (2)

125 65 -6- Claim for invention " A process for producing 1,1,1,3-tetrahalo-4-niethylpentane characterized by reacting tetrahalomethane with 3-methyl-1-butene by an addition reaction in the presence of a catalytic amount of a catalyst selected from metallic iron, copper II chloride, copper I chloride, iron (III) chloride, iron (II) chloride, iron (II) chloride with benzoin, ruthenium-II-triphenylphosphine complexes, organic peroxides and cobalt II salts. 2. The method according to item 1, characterized in that da / 3 is used as tetrahalomethane carbon tetrachloride.