DE1267684B - Method of making iron - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. CL:

C07c

German class: 12 ο - 25

Number: 1267 684

File number: P 12 67 684.5-42

Filing date: February 10, 1964

Opening day: May 9, 1968

The well-known methods of making irons are cumbersome and expensive, so that these compounds, which are very interesting fragrances per se, because of the high manufacturing costs in the fragrance industry, only to a very limited extent so far have been used. We have now succeeded in significantly simplifying or increasing the synthesis of the irons cheaper by using a new intermediate that is readily available and cheap.

The present invention relates to a method for the production of iron, which is characterized is that l, l-Dimethyl-2- [3-methyl-7-oxo-octadien- (3,5) -yl- (l)] - cyclopropane with such acidic agents and under such reaction conditions as are known for the cyclization of pseudojonon and pseudoiron to be applied to Jonon and Iron, respectively.

Treatment of the cyclopropane derivative with acidic agents causes the cyclopropane ring to break down resulting in the formation of a methyl group, ao at the same time takes place under the action of the acidic By means of the cyclization of the intermediate formed pseudoiron to iron. 1,1-Dimethyl-2- [3-methyl-7-oxo-octadiene- (3,5) -yl- (l)] -cyclopropane can thus be carried out in a single process using acidic agents stage cyclize directly to iron.

The conversion of the cyclopropane derivative into iron takes place with the same acidic agents as are known for the cyclization of pseudoirones and pseudoirones to form ions or irones. You can Bronsted acids, ie inorganic or organic acids such as phosphoric acid, sulfuric acid or mixtures of sulfuric acid and acetic acid or compounds of the Lewis acid type, eg. B. boron trifluoride or aluminum chloride, use. Buffer mixtures, e.g. B. Mixtures of phosphoric acid and monosodium phosphate. The acidic treatment of the cyclopropane derivative is carried out under the same conditions with regard to reaction temperature, reaction time and solvent as are customary for the cyclization of the pseudo-ionons or pseudo-irons. Favorable results are achieved, for example, with 84% phosphoric acid at temperatures below 10 ° C. or with a mixture of 84% phosphoric acid and monosodium phosphate at room temperature. The cyclization of pseudojonon and pseudoiron is described in detail and exhaustively, for example, in the two literature references mentioned below: Industrial and Engineering Chemistry, Vol. 8, 1946, pp. 546 to 548, and E. Gildemeister and Fr. H ο ffma η η, Die Essential Oils, 4th Edition, Vol. IHe, Akade Process for the Production of Iron

Applicant:

Firmenich et Cie., Geneva (Switzerland)

Representative:

Dr. W. Schalk, Dipl.-Ing. P. Wirth,

Dipl.-Ing. G. E. M. Dannenberg

and Dr. V. Schmied-Kowarzik, patent attorneys,

6000 Frankfurt, Große Eschenheimer Str. 39

Named as inventor:
Dr. Albert Eschenmoser,
Dr. Dorothea Felix, Zurich;
Dr. Max Stoll, Geneva (Switzerland)

Claimed priority:

Switzerland of February 11, 1963 (1681)

mie-Verlag, Berlin, 1963, pp. 377 to 382 and 400 to 401

The l, l-dimethyl-2- [3-methyl-7-oxo-octadiene- (3,5) -yl- (l)] -cyclopropane serving as an intermediate for the new process can be obtained by treating pseudo-jonon with compounds, which are capable of attaching to the double bond of the terminal isopropylidene group of the pseudojonon add or introduce a methylene group.

Such compounds can be haloalkyl metal compounds such as bis-haloalkyl zinc, e.g. B. Bischloro-, bisbromo- or bisiodomethylzinc or bischloro-, bisbromo- or bisiodomethylzinc; Haloalkylaluminum dialkyls, z. B. use chlorine, bromine or iodomethyl diethyl aluminum or chlorine, bromine or iodoethyl diethyl aluminum. The attachment the methylene group can also be done by means of methylene iodide and zinc iodide.

The formation of the cyclopropane ring succeeds in excellent yield if one uses pseudo-jonone Diazomethane in the presence of metal salts that behave like Lewis acids and are capable of with Diazomethane react with the release of nitrogen, such as zinc or aluminum halides and Mono- or dialkyl aluminum halides, e.g. B. zinc bromide or iodide, aluminum chloride, mono- or Diethylaluminum chloride, bromide or iodide, or cuprous chloride can act.

809 548,426

3 4

You can also use diazomethane together with boron iodide solution. The content of bis (iodomethyl) zinc

Acid esters, especially lower alkyl esters, were determined iodometrically. The solution was about

turn around. 0.19 molar, which is about a 71% yield. loading

A favorable way of working for the production of pulled zinc iodide, corresponds to. By dilution l, l-Dimethyl-2- [3-methyl-7-oxo-octadien- (3,5) -yl- (l)] - 5 a 0.132 molar solution was prepared,

cyclopropane consists z. B. is that to the mixture b) 1020 ml of a 0.132 molar bis-0'odmethyl) -

from an essential solution of zinc iodide and a zinc solution were taken in a rotary evaporator

ethereal diazomethane solution at temperatures, moisture exclusion at a bath temperature of

which are below room temperature, e.g. B. at ^{0 0} C or -5 ⁰ C concentrated to about 200ml. In the narrowed Lödarunter, pseudojonon admits. The various encryption io measurement were 13.1 g of trans-pseudoionone (nl ⁰ = 1.5341;

Driving stages must be in a moisture-free indoor environment. X _max - 194 ηιμ; ε = 14500). One let

th atmosphere, e.g. B. under nitrogen, carried out the temperature of the reaction mixture on Zim-

will. The conversion of the zinc iodide increases with the diazo- mer temperature and then warmed it up

methane solution is under development and nitrogen for 2 hours at a bath temperature of 50 ⁰ C. To this leads to the formation of bis-0'odmethyl) -zinc. 15 poured the reaction mixture on ice, took it in

Compared to the known processes for the production of ether, shaking the essential extract of iron from pseudoiron, an essential corn is achieved with ice water, then with diluted ammonia, if for production and then with ice water until it was neutral. Iron can be assumed from pseudoiron, after drying the extract with sodium sulfate, since pseudoiron is more easily accessible than pseudoiron. 20 and the removal of the ether became the crude product. The pseudoiron required for the production of iron according to known Ver (13.8 g) from a Clais flask using a water jet is namely distilled from a methyl vacuum. 10.41 g of 1,1-dimethylcitral were produced, which, in turn, was only stepped and expensive by a multi- 2- [3-methyl-7-oxo-octadiene- (3,5) -yl- (1)] -cyclopropane Synthesis is available. In contrast, from bp 100 to 129 ° C / 0.05 Torr; n ' _D ° = 1.5162; pseudojonon is a much more accessible and 25 X _max = 294ηιμ (ε = 13300) obtained. Yield: 74.9% · cheaper substance obtained by condensation of citral. _x , is obtained with acetone. ^c > Manufacture of iron

In contrast to methylcitral, the citral is a 0.5 ml 84% phosphoric acid, which is used with a large-scale, cheap product, the z. B. was cooled as a mixture of ice and table salt, one dripped rule product for the vitamin A synthesis in large 30 is slowly prepared with constant stirring with a magnet quantities. Citral is recently also stirred 100 mg of l, l-dimethyl-2- [3-methyl-7-oxo-octa from a dien- (3,5) -yl- (l)] -cyclopropane, which is available in large quantities the starting material that is cheap to react, the /? - pinene, is obtained by large-scale mixing for 30 minutes in the cold and heated technical syntheses. The present it then 10 minutes to 50 ° C. The train of thought on which the invention is based consisted of 35 cyclization product was poured onto ice and the expensive pentane was then added to the iron synthesis. The extract was switched off twice via the pseudoiron and via the pseudojonon with saturated sodium bicarbonate solution and twice a lot cheaper, an economically much with saturated saline solution was shaken out, with a cheaper synthesis of the iron. The known method, dried after sodium sulfate and freed from pentane, by cyclization of pseudo-iron produced by distillation of the crude product in a Kugelrohr iron is a very expensive product, which gave a yellow oil with a bp. 90 ° C./0.1 Torr; precisely because of its high price only in limited £ - 1.5081. Yield of cyclization product: about temp can be used in perfumery. 80% · It was determined by gas chromatography, even if in the method according to the invention that this product was about 56% trans-κ-iron, about 18% the yield of iron, based on pseudojonon, 45 cis-Λ-ΐΓοη and about 22% / 3-Iron, is smaller than in the direct cyclization of pseudo-. ■ \ ■) iron, so this difference is in the yields by e 1 s 1 e ρ much cheaper price of pseudoionone more than To 5 ml of 84% phosphoric acid, which made up in a. After the ice-common salt mixture according to the invention was cooled, one dripped the iron produced is several times cheaper 50 slowly 1 gl, l-dimethyl-2- [3-methyl-7-oxo-octadiene than that obtainable by the known syntheses ( 3,5) -yl- (l)] cyclopropane (see Example 1) and stirred the iron. Through the present invention, the mixture is then heated for 30 minutes with cooling, the fragrance industry has the option of giving the mixture to 50 to 10 minutes, a very interesting, but previously ^{heated to 55 0} C (bath temperature), then expensive on ice water Fragrance on a larger scale and also poured in 55, taken up in pentane, to be used once with Najenen cases in which the conventional trium hydrogen carbonate, shaken out several times with saline iron products because of their too high price solution, could not be used when dried with sodium sulfate. . and freed from pentane. The residue was im

Kugelrohr at 0.1 Torr and a bath temperature of

Example 1 60 90 to 100 ⁰ C distilled. Yield 720mg = 72%,

a) Production of the starting material "\ Γη '? ⁵ ηΆ ^DU "? Gas chromatography was

/τ.· / ·· j i_ i \ · T τ ν averages that the product obtained is about 60% trans-

(Bis (iodomethyl) zinc solution) _a . _{Iron> about 21} o _{/ o 0} ΐ ₅ . _Λ . _{ΐΓθη and about} a 12.5% / 9-Iron

A three-necked flask contained 60 g of zinc iodide.

200 ml of absolute ether with exclusion of moisture 65 B e i s ρ i e 1 3

dissolved in a nitrogen atmosphere. Under ice cooling

500 ml of ethereal 20 mg of l, l-dimethyl-2- [3-methyl-7-oxo-octadiene-

rhche diazomethane solution (about 0.8 n) in the zinc- (3,5) -yl- (l)] - cyclopropane (see example 1) were at

- 10 ° C was added dropwise to 1 ml of 84% phosphoric acid, and the mixture was then stirred at this temperature for 20 minutes. The red-brown, rather thick solution was poured onto a mixture of sodium hydrogen carbonate solution and ice, taken up in ether and shaken out several times with water. After the ethereal solution had been dried with sodium sulfate, the ether was removed and the residue was distilled in a bulb tube at a bath temperature of 90 to 100 ° C. in a high vacuum. Yield: 14 mg. It was determined by gas chromatography that the product obtained contained about 55% trans-Λ-οη, about 30 ° / ₀ cis - «- iron and about 11% β-iron .

Example 4

20 mg of 1,1-dimethyl-2- [3-methyl-7-oxo-octadien- (3,5-yl- (l)] -cyclopropane (see Example 1) were dissolved in 0.5 ml of pentane and added to 10 ° C. to a mixture of 0.5 ml of pentane and 1 ml of 65% strength sulfuric acid.After stirring for 1 hour at 10 ° C., the mixture was poured onto a mixture of ice and sodium hydrogen carbonate, taken up in pentane and worked as is Yield after distillation under high vacuum: 12 mg. The product obtained contained about 56% trans-a-iron, about 23% cis - «- iron and about 14% β-Ιτοη.

Claims (1)

Claim: Method of making iron, thereby characterized in that l, l-dimethyl-2- with such acidic agents and under such reaction conditions as are known in the art . are used for the cyclization of pseudo-jonon and pseudo-iron to form ion-ion or iron, treated. Considered publications: German Auslegeschrift No. 1 080 105; Chem. And Ind., 1955, p. 357; J. Am. chem. Soc, Vol. 81, 1959, pp. 247, 248; Vol. 82, 1960, pp. 4426, 4427; Fette, Seifen, Anstrichmittel, Vol. 57, 1955, pp. 595 to 600.