JPS6021138B2 - How to make yonon or ilon - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel method for producing ionone or ilone from propargyl type alcohols.

A typical method for totally synthetically producing ionon is known, which consists of the following steps [US Pat. No. 2,861,
No. 109, British Patent No. 948,752, J. ○rg.
Chem. , 23, 153 (1958), Angew・
Chem. , 72, 869 (1960), etc.]. [1' step of ethynylating methylheptenone, [2] reacting the obtained 3,7-dimethyloct-6-en-1-yn-3-ol with diketene or improbenyl ether, {3' rearrangement of the product] and ■ a process of ring-closing pseudonyone.

Diron is produced by using 5,6-dimethylheptane-2-one in place of hetylhebutenone in the above process via the corresponding intermediate.

The diketene or improbenyl ether used in the above method is a C3 extender that is generally preferred in the synthesis of terbene compounds using Carroll rearrangement reaction or Kleiseso rearrangement reaction, but it is relatively expensive; The disadvantage is that the reaction operation is complicated, and therefore the C3 elongation step accounts for a high proportion of the manufacturing cost of the terbene compound.

The production of the above-mentioned ionone and ilon by applying this reaction is no exception. The present invention has solved this problem, and according to the present invention, the following formula (m) (wherein R represents a hydrogen atom or a methyl group).

bropargyl-type alcohol represented by
The following formula (
By ring-closing Q・8,y・6 monounsaturated Kent represented by Indicates a double bond.

ionon (R=H) or ionon (R=CH3) represented by (the same applies hereinafter) is produced. The first feature of the present invention is that
By simply heating the propargyl type alcohol of the formula (m), Q.8,y.6 monounsaturated kent (pseuidononone or pseudodiron) of the formula (0) can be obtained in one step, and diketene or improbenyl alcohol can be obtained in one step. There are great economic and process benefits due to the fact that the use of esters can be omitted and the reaction operation is simplified.

The second feature is that the propargyl-type alcohol of formula (m) used in the present invention can be prepared easily and inexpensively, and in combination with the first feature mentioned above, it is extremely advantageous for the total synthetic production of ionone or ionone. It is to be. The propargyl type alcohol of formula (m) used in the present invention is a new compound, and is an organic halide represented by the following formula (V) (in the formula, x is a halogen atom), that is, prenyl halide or 2,3-dimethyl-1-halo- It can be produced by etynylating an unsaturated Kent represented by the following formula (W) obtained by the reaction of 2-butene with mesityl oxide and/or isomesityl oxide.

In the present invention, the halide of formula (V) is preferably chloride or bromide because of its ease of availability.

Mesityl oxide and isomesityl oxide are usually produced industrially as a mixture of the two by dehydration of diacetone allure, which is a dimer of acetone, and can be separated into each using the difference in boiling point. , separation is not necessarily necessary for the purpose of producing propargyl-type alcohols of formula (m). The reaction between the organic halide of formula (V) and mesityl oxide and/or isomesityl oxide is generally carried out by reacting the ketone and the organic halide with an amine compound, quaternary ammonium salt or phosphonium compound in the presence of an alkaline condensing agent. This reaction can be carried out by a known method of producing a substituted ketone by reacting with a catalytic acid as a catalyst. The alkaline condensing agent is preferably sodium hydroxide or potassium hydroxide, either as such or in an amount of about 40 to 65
It is used in the form of an aqueous solution in an amount of about equimolar to about 1 molar relative to the organic halide of formula (V). Preferred examples of the catalyst include tetrabutylammonium chloride, trimethylbenzylammonium chloride, trimethyllauryl ammonium chloride, trimethylstearylammonium chloride, methyltricyclohexylphosphonium bromide, etc. It is used in an amount of 0.001 mol% to 20 mol%. The reaction temperature can be arbitrarily selected within the range of 0 to 100 oo. Regardless of whether mesityl oxide or isomesityl oxide is used in the reaction, the product has an isomer relationship with respect to the double bond at the position indicated by the dotted line in the formula (W). and (N-2) are a mixture of unsaturated Kents. When ethynylation is carried out under certain conditions, unsaturated Kent of formula (W-2) is isomerized to unsaturated Kent of formula (W-1) in the ethynylation reaction system.

This is a noteworthy fact that further enhances the advantage of the process of the present invention for producing ionone or ionone from the propargyl type alcohol of formula (m). Therefore, the formula (W-1
) and the unsaturated Kent of formula (W-2) are not required to be separated from the reaction product, respectively, in the present invention. However, the ethynylation method that does not cause the above isomerization (
If, for example, a reaction with an ethynyl Grignard reagent) is employed, it will be necessary to separate off the ketone of formula (N-2) or to isomerize it to the ketone of formula (N-1). The ketones of formulas (W-1) and (W-2) can be separated by precision distillation.

Isomerization of the ketone of formula (N-2) can also be performed on the separated ketone, but the ketone of formula (W-1) must have a lower boiling point than the ketone of formula (W-2). Therefore, the ketone of formula (W-1) can be continuously obtained by distilling the ketone mixture under isomerization conditions in the presence of an isomerization catalyst having a boiling point higher than that of these ketones. Isomerization catalysts include, for example, benzenesulfonic acid, p-toluenesulfonic acid, laurylsulfonic acid, p-tolylic acid, 4-nitro-m-toleic acid, 4-hydroxybenzoic acid, 4-nitroisophthalic acid, cyclohexanecarboxylic acid, adipic acid, 1 ，
Acids such as 2-hydroxystearic acid, benzylic acid, p-nitrocinnamic acid, diglycolic acid, indolebutyric acid, metaphosphoric acid, phenylphosphinic acid, and sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide, and sodium carbonate. , potassium carbonate, sodium acetate, potassium acetate, calcium carbonate, magnesium carbonate,
Lithium amide, sodium amide, potassium amide,
sodium methoxide, sodium t-butoxide,
Triethylamine, monoethanolamine, diethanolamine, triethanolamine, 1,5-diazabicyclo[3.4.0]/nene-5, 1,5-diazabicyclo[5.4.0] undecene-5 (abbreviated as DBU)
, 1,4-diazabicyclo[2.2.2]octane (
(abbreviated as DABCO), hexamethylenetetramine, etc., and the amount used is determined according to the isomerization method. Note that the alkali metal hydroxide as a base catalyst is 2
used in combination with the quaternary ammonium or phosphonium salt catalysts mentioned above for the reaction of organic halides of formula (V) with mesityl oxide and/or isomesityl oxide in the form of a 0-60% aqueous solution; It is desirable to do so from the viewpoint of isomerization reaction rate. The unsaturated ketone of formula (W), particularly the ketone of formula (W-1), can be henitylated by a method known per se as a method for producing a compound having a propargyl alcohol structure by ethynylation of ketones (for example, U.S. Patent No. 3,08
No. 2,260, No. 3,496,240, JP-A No. 50-159308).

Although ethynylation methods using alkali metal or alkali metal acetylides or using ethynyl Grignard reagents may be suitable for small-scale reactions, on an industrial scale the preferred ethynylation method is In the presence of a catalytic amount of a strongly basic compound of metal, N,N
- In an organic polar solvent such as dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, tetrahydrofuran, dimethyl ether, dimethyl ether, methyl ethyl ether, anisole, dioxane, or in liquid ammonia or a mixed solvent thereof, acetylene is converted to formula (W). This method involves reacting with unsaturated Kent. In this method, propargyl alcohol is produced at low cost, post-treatment is easy, and the unsaturated ketone of formula (W-2) is isomerized to the ketone of formula (W-1) in the ethynylation reaction system. It is industrially advantageous. Acetylene is expressed by the formula (
It is preferable to use 0.5 mole or more per mole of unsaturated Kent (W), and the reaction temperature is suitably -30 oo to 13,000. Generally speaking, the reaction in which propargyl alcohol is heated and rearranged into an unsaturated Kent, which is a structural isomer, is known as the Oxy Cope rearrangement reaction. Am. Chem. S's. ，
86,5017,5019 (1964), 87,11
50 (1965), 92, 2404 (1970)].

However, the propargyl alcohol of formula (m) in the present invention has never been subjected to an Oxycope rearrangement reaction, and it is not known that ketones having a terbene skeleton can be obtained by this reaction. In the present invention, pseudonyone or pseudodylon of formula (b) is expressed as formula (m)
The direct heating of propargyl-type alcohols makes it possible to produce ionone or ionone very easily and cheaply compared to conventional methods using C3 extenders. The rearrangement reaction of the propargyl type alcohol of formula (m) obtained by the above-mentioned ethynylation can be carried out in a liquid phase or a gas phase.

Reaction temperatures ranging from 100 to 400 pm are used;
From the viewpoint of reaction rate and selectivity, 1 for liquid phase reaction.
00~250 o'clock ○ Especially 130~230 o'clock, for gas phase reactions it varies depending on the residence time, but 250~400 o'clock
A range of qo is preferred.

The reaction is preferably carried out under an atmosphere of an inert gas such as nitrogen or helium. Although it is not essential to use a solvent in the reaction in a liquid phase, solvents that are stable under rearrangement reaction conditions and do not participate in the reaction, or that improve selectivity, such as dimethyl sulfoxide, diethyl sulfoxide, tetramethylene sulfoxide, dimethylformamide, Molecules such as dimethylacetamide, diethylformamide, diethylacetamide, pyrrolidone, N-methylpyrrolidone, N-ethylpyrrolidone, gocaprolactam, hexamethylphosphoramide, hexaethylphosphoramide, trimethylphosphate, toluethylphosphate, etc. A trough organic compound having a sulfoxide group (-3S→○), an amide group (RAP:○), and a phosphoryl group (RAP:○) can be used.

These solvents are effective in improving selectivity, and the formula (m)
It is practical to use the volume (capacity) in the range of 0.5 to 2 with respect to the propargyl type alcohol. The rearrangement reaction product is generally Q・8,y・6 represented by the formula (b)
-In addition to unsaturated Kent, it contains Q.B,6.-unsaturated Kent as an isomer represented by the following formula (0').

Unsaturated Kent of formula (0') is Q・6,y・6 of formula (0)
- It is possible to isomerize to unsaturated Kent, thereby increasing the yield of ionone or ionone.

This purpose can be achieved by isomerizing the rearrangement reaction product in the presence of a rhodium compound, ruthenium compound, iodine-containing ammonium compound, bromine-containing ammonium compound, or iodine as an isomerization catalyst prior to the ring-closing reaction. was discovered. Examples of the most preferred isomerization catalysts are rhodium chloride hydrate, ammonium iodide, hydriodide salts of amines, iodine, and although not as highly active as these catalysts, tris(triphenylphosphine)
Rhodium chloride, tris(triphenylphosphine)ruthenium chloride, rhodium acetylacetonate, ruthenium acetylacetonate, ruthenium chloride hydrate, tris(pyridine)rhodium chloride, ammonium bromide, halogenated bromine salts of amines, etc. is also effective as an isomerization catalyst. The amount of catalyst used is about 0.05 to about 1% by weight based on the total amount of ketones of formulas (0) and (b').
is appropriate. The isomerization reaction can be carried out at a molecular weight of 0 to 25,000, but a range of 50 to 20,000 is preferred. Among the above isomerization catalysts, iodine-containing ammonium compounds, bromine-containing ammonium compounds, iodine, and the like do not have an adverse effect on the rearrangement reaction of the propargyl alcohol of formula (m). Therefore, in the rearrangement reaction of propargyl type alcohol and the isomerization of the unsaturated atom of formula (0'), the temperatures of both reactions overlap if an isomerization catalyst that does not adversely affect the rearrangement reaction is used. It can be carried out in the same reaction system within the range. In this case, as a solvent that does not inhibit the isomerization reaction and improves the selectivity of the rearrangement reaction of propargyl alcohol, the above-mentioned amide group or
It is desirable to use a polar organic compound having a phosphoryl group where =◯.

The ring-closing reaction in which pseudonylon or pseudodylon of the formula (0) thus obtained is ring-closed in the presence of an acidic catalyst to produce pseudonylon or pseudylon can be carried out by a conventional method. Temperature -3 in the presence of acidic catalysts such as zinc, with or without solvents such as hydrocarbons, alcohols, etc.
It can be carried out at 0 to 150°C.

Depending on the reaction conditions such as the type and concentration of the ring-opening agent, the product is ionone or ionone represented by the following formula (1),
It is an isomer with respect to the double bond at the position shown by the dotted line, that is, any one of Q-, B-, and y-isomers, or a mixture thereof.

Next, the present invention will be specifically explained with reference to Examples.

Example 1'1) Production of unsaturated Kent (W) In a solution of 600 g of sodium hydroxide and 490 g of water, 0 g of mesityl oxaside and 0 g of prenyl chloride (purity 83
．． 71%) 520 liters and 25 liters of trimethylstearylammonium chloride were added, and the reaction was carried out for 2 hours while keeping the lights on (the reaction temperature rose to 70 qo).

The reaction mixture was poured into water and extracted with ethyl ether, and the ether layer was washed with water and dried over anhydrous ramie. After distilling off the solvent from the ether layer under reduced pressure, the remaining 1,250 yen was distilled to recover unreacted mesityl oxide, and 3-
560 g of a 2.5:1 mixture of isoprobenyl-6-methyl-5-hepten-2-one and 3-isopropylidene-6-methyl-5-hepten-2-one was obtained. The mixture was distilled using a precision distillation column with 30 theoretical plates, and the boiling point was 32.
3-isoprobenyl-6-methyl-5-hepten-2-one (410 yen) is obtained from crab meat with ~34 qo/0.2 skin Hg, and 3-isopropylidene-6 from crab meat with a boiling point of 35~38 oo/0.2 rib Hg. -Methyl-5-heptene-2
-on (130 evenings) were obtained, respectively. The above 3-isopropylidene-6-methyl-5-hepten-2-one 130
The mixture was put into the closed bottom of a precision distillation column with 3 theoretical plates, together with 2 liters of DBU (isomerization catalyst), and distilled while isomerizing at a reflux ratio of 10/1 under a reduced pressure of 3 tons of Hg, and the distillate was obtained. I got 114 evenings.

According to gas chromatography-analysis, this distillate has 3
It was a mixture of -isoprobenyl-6-methyl-5-hepten-2-one (98.5%) and 3-isopropylidene-6-methyl-5-hepten-2-one (1.5%). '21 Production of propargyl alcohol (m) 5
In the three-necked flask, 70 g of metallic sodium was added to 3 g of liquid ammonia, and acetylene gas was blown into the flask.

When the reaction solution turned gray, the injection of acetylene gas was stopped, and a small amount of 3-isopropylidene-6-methyl-5
3-isoprobenyl-6-methyl-5-hepten-2-one containing 2-hepten-2-one is added,
Then, acetylene gas was blown into the mixture and the reaction was carried out at -33°C for 3 hours. After removing ammonia, the reaction mixture was neutralized with ammonium chloride, poured into water, and extracted with ether. After drying the ether layer with anhydrous ramie salt, the solvent was removed under reduced pressure. The residue 524 was distilled under reduced pressure to obtain a crab fraction 519 having a boiling point of 59 to 6.1°C/0.5 willow Hg. This crab content is 3-isoprobenyl-6-methyl-5-hepten-2-one (2% by weight).
), 3-isopropylidene-6-methyl-5-hepten-2-one (8% by weight) and 4-isoprobenyl-3
, 7-dimethyl-6-octen-1-yn-3-ol (9% by weight). The structure of the product was confirmed by the following method.

Infrared absorption spectrum (Ki-1) 3440 (1OH),
3300, 2120, 1640, 1450, 1378,
1128, 1030, 900 nuclear magnetic resonance spectrum 1.40 (s, group, 1,60 (s, Hoso, C Koichi) 1.72, 1.73 (each s, 9th, CH3-)
2.00-2.47 (m, 3 days, one CH2-CH-)2
．． 30 (s, IH, 1C-CH) ca. 4.8
3-5.00 (m. milk day, ECH-, = C ratio)'3}
Preparation of pseudonymone 4-Isobrobenyl-3,7-dimethyl-1-octyne-6-en-3-ol (purity 90%) was placed in a 3-necked flask on a desk, and heated at an internal temperature of 150°C under a nitrogen atmosphere. The rearrangement reaction was carried out by heating for a certain period of time.

The reaction solution is vacuum distilled as it is to reduce the bp containing unreacted raw materials.
7 is less than 0 (0.16 to 0.17 side Hg) and 6,10-dimethyl-3 which is a rearrangement product.
, 5,9-undecatrien-2-one and 6,10
-dimethyl-3,6,9-undecatriene-2-one bp76~9oC/0.16~0.17 Yanagi Hg
A Takanada point fraction of 70% (purity 94.7%) was obtained. The structure of the rearranged product was confirmed as follows. The mixture was separated into two components by preparative gas chromatography, and one component was commercially available 6,10-dimethyl-3,5, whose infrared absorption spectrum and nuclear magnetic resonance spectrum data
Consistent with those of 9-undecatrien-2-one, and in the presence of a phosphoric acid catalyst in the step described below,
Since the ring-closing reaction gave Q-ionone and 8-ionone, it was confirmed that it was 6,10-dimethyl-3,5,9-undecatrien-2-one. The structure of the other component was determined by the following method: 6,10-dimethyl-3,6
, 9-undecatrine-2-one. Infrared absorption spectrum (Ka-1) 1675 1623 1440, 1376 1360,
1255 nuclear magnetic resonance spectrum 1.60 (s, unit), 2
．． 11 (s, thin), 2.72 (m, calm), 5.01 (m
, IH), 512 (m, IH), 5. Place (m, IH),
6.40 - 6.90 (m, IH) '4' Production: Put 30 m of 85% phosphoric acid into a 100 m three-necked flask.
6,10-dimethyl-3 at a temperature of -5 to 0°C while
, 5,9-undecatriene-2-one (pseudoyone) was added dropwise for 10 minutes.

After dropping, incubate at that temperature for 15 minutes, then heat to 35-4℃.
I worshiped Iso for 10 minutes. The reaction mixture was poured into ice water and extracted with ether, and the ether layer was dried over anhydrous magnesium sulfate. The ether was then distilled off under reduced pressure to obtain 9.2% of a light brown oil with an aroma. This is gas chromatography-analysis (PEG2 M, column temperature 110q
As a result of o), it contained 82% Q-ion, 11% 8-ion and 7% yo-non. Example 2 '1} Production of unsaturated ketone (W) The reaction was carried out in the same manner as '1' of Example 1, except that 2,3-dimethyl-1-chloro-2-butene 5902 was used instead of prenyl chloride 520. Ta.

The reaction mixture was poured into water and extracted with ether, and the ether layer was washed with water and dried over anhydrous potato salt. After removing the solvent from the ether layer under reduced pressure, the remaining portion was distilled to recover unreacted mesityl oxide, and high boiling point substances (boiling point 92.0-95
．． 3-isoprobenyl-5 as yC/5.5 leg Hg)
, 6-dimethyl-5-hepten-2-one and 3-isopropylidene-5,6-dimethyl-5-hepten-2-one were obtained. ■ Production of propargyl type alcohol (m) 3-isoprobenis-6-methyl-5-hef.

Ten-2-on 517 Instead of evening 3-Isopro Venice-
The ethynylation reaction was carried out in the same manner as in Example 1 [2-] except that 5,6-dimethyl-5-hepten-2-one was used. After removing ammonia, the reaction mixture was neutralized with ammonium chloride, poured into water, and extracted with ether. After drying the ether layer with bitter salt, the solvent was removed under reduced pressure. Furthermore, the residue is distilled to a boiling point of 89-9〆○/
A fraction of 585 ml of 2.3 Hg was obtained. This crab content is 3-isoprobenyl-5,6-dimethyl-5-hepten-2-one (3.5% by weight), 3-isopropylidene-5,6
Dimethyl-5-hepten-2-one (12.5% by weight)
, 4-isoprobenyl-3,6,7-trimethyl-1-octyne-6-eso-3-ol (weight %). The structure of the product was confirmed by the following method. Infrared absorption spectrum (skin-1) 3440 (1OH), 3
300,3070,1639 1450,1375 9
00 Nuclear Magnetic Resonance Spectrum 1.41 (s, 1.56 (s, Misaki, CH3-) 1,74 (eachs, Sawa, CH3-)!2,2
1 to 2.45 (m, thin, -CH2-CH-) 2.31
(s, IH, 1C...CH) 4.86 (s,
2 days, = C ratio) '3} Production of pseudodilon 4-isobu-benyl-3,6,7-trimethyl-1-octyne-6-en-3-ol 226 days (purity 84%)
was placed in a 500-ship three-necked flask under a nitrogen atmosphere.
A rearrangement reaction was carried out by heating at an internal temperature of 165 qo for 4 hours.

The reaction solution was vacuum distilled as it was to remove low-boiling components including raw material unreacted materials, and then high-boiling components (boiling points 103 to 105) were removed.
0/0.7 Yanagi Hg), target objects 6,9,10-trimethyl-3,5,9-undecatrien-2-one and 6,9,10-trimethyl-3,6 with a composition ratio of 1:1.5. , 9-undecatriene-2-one (purity: 93%) was obtained. These were a mixture of 3 to 7 cis and trans isomers each. The structure of the product was confirmed as follows. Infrared absorption spectrum (inhibition-1) 1718, 1668, 1630, 1587, 1440,
1376,1360,1255 1150 970, 6,9,10-trimethyl 3 in total 5 mass spectra
,5,9-undecatrien-2-one and 6,9,
10-trimethyl-3,6,9-undecatriene-2
The difference in the characteristic fragments of -on is that the former is m/e1
24, 109, 83, 55, 43 and 41 (100%
) is strong, whereas the main fragment of the latter is m/e43 (100%).

[4] Production of 6, obtained by separating in the same manner as {3- in Example 1,
5 quarts of 9,10-trimethyl-3,5,9-undecatryen-2-one were added dropwise onto 15 quarts of 85% phosphoric acid while maintaining the reaction temperature at 30 to 35 quarts.

After the dropwise addition, the mixture was kept at that temperature for 10 minutes, and then the reaction mixture was poured into ice water and extracted with ether. From the ether layer
The oil was distilled off, and the oily residue was distilled under reduced pressure to obtain an oil content of 3.2 mm (boiling point 104-110
0C/2.8 side Hg) was obtained. Example 3 Example 1 {
1} and 4-isoprobenyl-3,7-dimethyl-6-octyne-6ene- prepared in the same manner as (2}
3-ol (5 [) and various additives shown in Table 1 (1
The mixture of 5 above) was kept at a temperature of 16500 for 4 hours under nitrogen atmosphere.

6,10-dimethyl-3,5,9 which is a rearrangement reaction product
The yield of the mixture of -undecatrien-2-one and 6,10-dimethyl-3,6,9-undecatrien-2-one was measured by the internal standard method using gas chromatography (PEG 20M, column temperature 170o○). did.

The results are shown in Table 1. table· It was conducted for 10 days with 1 manjo.

The obtained pseudopyrofluoride was dissolved in 50% dry benzene, and boron trifluoride was gradually blown into the solution at a temperature of 0 to 5° C. while stirring. After lighting for another 10 minutes, cooled 10% sodium hydroxide aqueous solution 5 was added and extracted several times with benzene. The extract layer was dried over anhydrous magnesium sulfate, benzene was removed by evaporation, and then distilled under reduced pressure.
An oil content of 1.5% consisting of 90% Q-ionone was obtained. Example 4 4- prepared in the same manner as m and {2) of Example 2
A mixture of isopobenyl-3,6,7-trimethyl-1-octyn-6-en-3-ol (5) and the additives shown in Table 2 (15 mice) was added to 165q under a nitrogen atmosphere.
The rearrangement reaction was carried out by keeping the temperature at 100°C for 4 hours.

The product 6,9,10-trimethyl-3,5,9-
The yield and selectivity of the mixture of undecatrien-2-one and 6,9,10-trimethyl-3,6,9-undecatrien-2-one are shown in Table 2. Table 2 The ring-closing reaction was carried out with boron trifluoride in the same manner as in Example 3, except that the obtained pseudodilon was used instead of pseudononone, and the oil content was 1.6% consisting of 92% Q-dilon.
I got the evening.

Example 5 300ml of 4-isoprobenyl-3 was added to my two-necked flask.
, 7-dimethyl-1-octyne-6-en-3-ol (48%) and N-methylpyrrolidone (160%) were added, and the reaction was carried out under a nitrogen atmosphere by maintaining the temperature at 165q0 for 4 hours with a light on.

The reaction mixture was distilled as it was, and 6,1
A mixture of 0-dimethyl-3,6,9-undecatrien-2-one [denoted as (D')] and 6,10-dimethyl-3,5,9-undecatrien-2-one [denoted as (D)] Got 30.2 evenings.

The ratio of (0') to (0) was 93.2:6.8. (
Infrared absorption spectrum of (A-1) 2960,2
920, 2850, 1715, 1675, 1625, 1
440, 1360, 1255, 1160, 1110, 9
Infrared absorption spectrum of 70 (b) (Ki-1) 2960
,2910,2820,1660,16251585,
1440, 1360, 1250, 1155, 970, 8
8520 In my three-necked flask, I put 5 of the above ketone mixtures,
Iodine (o.o.
The isomerization reaction was carried out at the reflux temperature of ethanol while keeping the lights on.

Changes in the ratio of (ro') and (ro) in the reaction mixture over time were observed by gas chromatography (PEG 20M, column temperature 1700
0). The results are shown in Table 3. Table 3 Next, 6,10-dimethyl-3,6,9-undecatrien-2-one and 6,10-dimethyl-3 with a composition ratio of 5.7:94.3
,5,9-undecatriene-2-one20
The solution was dissolved in 30% n-hexane and this solution was added dropwise to a mixture of 50% sulfuric acid and 20% n-hexane.

The reaction temperature was maintained at around -20 oo. After the dropwise addition was completed, the reaction temperature was maintained at 0°C, and then the reaction mixture was poured into ice water.
- Extracted several times with hexane. The extract layer was dried over anhydrous magnesium sulfate, n-hexane was removed by evaporation, and then distilled under reduced pressure to obtain an oil containing 94% of 8-ionone. Example 6 Mixture of 6,10-dimethyl-3,6,9-undecatrien-2-one (0') and 6,10-dimethyl-3,5,9-undecatrien-2-one (b) [composition ratio (
An isomerization reaction was carried out under the conditions shown in Table 4 using 5' of (b')/(b)=93.2'6.8].

The results are summarized in Table 4. Table 4

Claims (1)

[Claims] 1 Propargyl type alcohol represented by the following formula (III) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ 100 to 40
The following formula (II) obtained by rearrangement at a temperature of 0°C ▲ Formula,
There are chemical formulas, tables, etc. α, β, γ, δ represented by ▼
- A method for producing ionone or yron represented by the following formula (I) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ characterized by ring-closing unsaturated Kent in the presence of an acidic catalyst (the above formula (I)
, (II) and (III), R represents a hydrogen atom or a methyl group, and the dotted line in formula (I) represents that one of the indicated positions is a carbon-carbon double bond) . 2 The propargyl type alcohol represented by formula (III) is an organic compound represented by the following formula (V) ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (wherein X is a halogen atom and R is a hydrogen atom or a methyl group) The following formula (IV) is obtained by the reaction of a halide with mesityl oxide and/or isomesityl oxide. There are mathematical formulas, chemical formulas, tables, etc. (R in formula (IV) has the above meaning, and the dotted line indicates this. (indicating that either one of the positions indicated is a carbon-carbon double bond) The method for producing yonon or iron according to item 1.