JPH0570449A - Production of sex pheromen of stinkbugs belonging to nezara and acrosternum species - Google Patents

Abstract

PURPOSE:To selectively obtain the required Z-isomer in a short process and provide a sex pheromone of stinkbugs belonging to the Nezara and Acrosternum species from inexpensive and readily available raw materials by reacting a specific epoxyketone with a specified phoshonium salt in the presence of a base. CONSTITUTION:An epoxyketone expressed by formula I, i.e., cis-,trans-1- acetyl-3,4-epoxy-4-methylcyclohexane is reacted with a phosphonium salt [e.g. triphenyl (4-methyl-3-pentenyl)phosphonium iodide] expressed by formula II (Ph is phenyl; X is halogen) in the presence of a base (e.g. methyl-lithium or sodium hydride) to afford a sex pheromone of stinkbugs belonging to the Nezara and Acrosternum species expressed by formula III, i.e., (Z)-cis,trans-2-(3',4'- epoxy-4'-methylcyclohexyl)-6-methylhepta-2,5-diene. The epoxyketone expressed by formula I is obtained by reacting a compound expressed by formula IV with m-chloroperbenzoic acid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to the sex pheromone of blue stink bug (Z) -cis, trans-2- (3 ', 4').
-Epoxy-4'-methylcyclohexyl) -6-methylhepta-25-diene.

[0002]

BACKGROUND OF THE INVENTION So far, (Z) -cis, trans-2- (3 ', 4'-epoxy-4'-methylcyclohexyl) -6-methylhepta-2,5- which is a sex pheromone of blue stink bugs. As the method for producing the diene, J. Che
m. Soc. Chem. Commum. , 414 (1
987)

[Chemical 4] And Synthesis, 537 (1989).

[Chemical 5] Is listed.

[0003]

As a method for producing the sex pheromone, the above-mentioned method of Chemical formula 4 produces equivalent amounts of unnecessary double bond sites of E-form, and the method of Chemical formula 5
Six steps are required until the final product is obtained, and the total yield is 26%. None of these methods are necessarily sufficient for selectively obtaining the desired Z isomer in a short process.

[0004]

In view of such a situation, the inventors of the present invention have taken the above-mentioned sex pheromone into a necessary Z-step in a short process.
As a result of extensive studies to develop a production method for selectively obtaining isomers, the inventors have found that the object can be achieved by using the following method, and have completed the present invention.

That is, the present invention has the structural formula

[Chemical 6] With an epoxy ketone represented by the general formula:

[Chemical 7] [In the formula, Ph represents a phenyl group, and X represents a halogen atom. ] And a phosphonium salt represented by the following formula are reacted in the presence of a base:

[Chemical 8] Blue stink bugs ( Nezara and Ac
method for producing (Z) -cis , trans-2- (3 ', 4'-epoxy-4'-methylcyclohexyl) -6-methylhepta-2,5-diene, which is a sex pheromone of R. rosternum species. Inventive method).

The epoxy ketone represented by the chemical formula 6 may be a cis isomer, a trans isomer, or a mixture thereof, but preferably the structural formula:

[Chemical 9] It is a 1'S body represented by.

In X of the general formula 7, the halogen atom is chlorine atom, bromine atom or iodine atom, preferably bromine atom or iodine atom.

As the base used in the method of the present invention, the phosphonium salt represented by the general formula 7 is Ph ₃ P-
A group capable of generating an anion at the α-methylene group to which the group is bound, such as methyllithium,
Examples thereof include organic lithium compounds such as n-butyllithium and inorganic bases such as sodium hydride.

The method of the present invention will be described in more detail. First, by reacting a phosphonium salt represented by the general formula 7 with a base, the structural formula 10

[Chemical 10] The phosphorane represented by is generated in the reaction system, and then
By reacting the epoxy ketone represented by the structural formula:
The sex pheromone represented by the structural formula 8 can be obtained.

The amount of the base used in the method of the present invention is usually 0.1 to 1 mol, preferably 0.5 to 1 mol, based on 1 mol of the phosphonium salt represented by the general formula. The amount of the epoxy ketone represented by the structural formula 6 is usually 0.3 to 10 with respect to 1 mol of the base.
It is in the molar range.

The method of the present invention is usually carried out in a solvent,
As the solvent used, for example, hexane, heptane, benzene, an aliphatic or aromatic hydrocarbon such as toluene,
Examples thereof include linear or cyclic ethers such as dimethyl ether, diisopropyl ether, tetrahydrofuran and dioxane, and a mixture thereof.

In the method of the present invention, the reaction temperature of the phosphorane represented by the general formula 7 and the base is usually -100 to 70 ° C, preferably -80.
The reaction time is usually 30 minutes to 6 hours, and it is advantageous to carry out the reaction under an atmosphere of an inert gas such as helium, nitrogen or argon.

In the method of the present invention, the phosphorane represented by the structural formula (10) formed in the reaction system is reacted with the epoxyketone represented by the structural formula (6) as it is without isolating it. The sex pheromone shown can be produced. Further, this reaction is generally accomplished by adding the epoxyketone represented by the structural formula 6 to the phospholane represented by the structural formula 10 previously prepared by the above-mentioned method. But it doesn't matter.

In the method of the present invention, the reaction between the epoxyketone represented by the structural formula 6 and the phospholane represented by the structural formula 10 is carried out by reacting the epoxyketone represented by the structural formula 6 without solvent. Although it can be used for the above, it is usually used after diluting with the above solvent, and the reaction temperature is usually in the range of -100 to 100 ° C, preferably -50.
To 80 ° C., and the reaction time range is usually 1 hour to 24 hours.
It is time, and it is advantageous to carry out under an atmosphere of an inert gas such as helium, nitrogen or argon.

After the reaction is completed, the reaction solution is poured into water, an aqueous solution of ammonium chloride, dilute hydrochloric acid or the like, the organic layer is extracted and separated, and if necessary, washed with water and / or dried over anhydrous sodium sulfate, magnesium sulfate or the like, and used as a solvent. The desired pheromone can be obtained by carrying out a post-treatment such as distillation, and if necessary, purifying it by operations such as chromatography and distillation.

The epoxyketone represented by the structural formula (6), which is the starting material in the method of the present invention, can be obtained by, for example, the method described in the above-mentioned literature or J. Chem. Soc. P
structural formula obtained by the method described in erkin Trans 1,569 (1987)

[Chemical 11] It can be obtained by reacting the compound represented by with m-chloroperbenzoic acid according to a conventional method of epoxidation.

The phosphonium salt represented by the general formula 7 is described in J. Chem. Soc. , 539 (1961)
It can be obtained according to the method described or in accordance therewith.

[0018]

The present invention will be specifically described below with reference to examples and reference examples, but the present invention is not limited to the following examples.

Reference Example (Production of Epoxy Ketone Represented by Structural Formula 6) Methyl 4-methyl-3-cyclohexenyl ketone
While stirring in 100 ml of methylene chloride solution of 7.14 g, m-chloroperbenzoic acid (purity 80%) at 10 ° C or lower.
170 ml of methylene chloride solution of 11.2 g was added dropwise.
After the dropping is completed, the temperature of the reaction solution is brought to room temperature (about 20 ° C.)
Stir overnight. The reaction solution was poured into 100 ml of 10% aqueous sodium thiosulfate solution, the separated organic layer was washed with saturated sodium bicarbonate water and water in that order, dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was chromatographed on silica gel. Purification by chromatography (developing solvent hexane: ethyl acetate = 3: 1) yielded 7.00 g of cis, trans-1-acetyl-3,4-epoxy-4-methylcyclohexane. yield
86%

N _D ^20.4 1.4682 IR ν _{max cm} ⁻¹ 2930 (s), 1704 (s),
1432 (m), 1380 (m), 1356 (m), 1
166 (s), 1122 (w), 1100 (w), 10
30 (w), 956 (w), 840 (m), 756
( _M ) NMR δ _H (CDCl ₃ ) 1.32 and 1.33
(S, 3H), 2.13 and 2.16 (s, 3H),
1.41-2.76 (m, 7H), 2.92-3.18
(M, 1H) GLC (column, OV-101, 50m x 0.25m
m, column temperature; 130 ° C., carrier gas; nitrogen gas, 1.00 kg / cm ² ): tr (trans) 15.
75 minutes (56%), tr (cis) 18.12 minutes (44
%) Thin layer chromatography (ether: hexane = 2:
3): Rf value 0.29 (trans), 0.22 (cis) Elemental analysis: Calculated value (C ₉ H ₁₄ O ₂ ) C; 70.10,
H; 9.15 (%) Found C; 69.98, H; 9.27.
(%) For identification of trans and cis isomers, NMR data of each was identified in the literature [Helv. Chim. Acta. , 62 , 216
8 (1979)].

Example Triphenyl (4-methyl-3-pentenyl) phosphonium iodide A suspension of 25.5 g of tetrahydrofuran was added to 180 ml of tetrahydrofuran at -10 ° C with n-butyllithium (1.
65N, hexane solution) (30.5 ml) was added dropwise. After stirring at the same temperature for 1 hour, cis, trans-1-acetyl-
3,4-epoxy-4-methylcyclohexane 2.7
10 ml of a 7 g tetrahydrofuran solution was added dropwise at -10 ° C. The reaction solution was stirred at the same temperature for 2.5 hours, poured into 200 ml of a saturated aqueous solution of ammonium chloride, and the resulting solid matter was filtered off. The filtrate was extracted with ether, washed with water and saturated brine in that order, the ether solution was dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was subjected to silica gel chromatography (silica 180 g, hexane: ethyl acetate = 2).
(E), (Z) -cis, trans-
0.93 g of 2- (3 ', 4'-methylcyclohexyl) -6-methylhepta-2,5-diene was obtained. yield
24% E / Z ratio 13/87

N _D ^20.4 1.4893 IR ν _{max cm} ^-1 2990 (s), 2945 (s),
1654 (w), 1436 (m), 1380 (m), 1
254 (w), 1112 (w), 1120 (w), 11
06 (w), 840 (w), 758 (w) NMR δ _H (CDCl ₃ ) 1.02-2.54
(M, 19H, δ = 1.32 and 1.33s, 1.6
3s) 2.67 (bt, 2H), 2.91-3.11.
(M, 1H), 5.08 (m, 2H) ¹³ C NMR (75MHZ, CDCl ₃ ) δ = 17.
72, 19.07, 19.24, 23.21, 2
3.84, 24.35, 24.58, 25.72,
26.23, 26.37, 26.88, 28.4
3, 29.24, 29.93, 30.10, 3
0.76, 34.55, 42.52, 57.08,
57.40, 59.40, 60.83, 122.
53, 123.31, 123.40, 123.8
8, 124.53, 131.39, 137.66,
137.66, 138.05 GLC (column, CBP-10, 25 m × 0.25 m
m, column temperature; 80 ° C. (2 minutes) + 6 ° C./minute up to 220 ° C. carrier gas; nitrogen gas, 1.00 kg
/ Cm ² ): tr (Z) 21.27 minutes, 21.56 minutes (87%), tr (E) 22.30 minutes, 22.60 minutes (13%) Elemental analysis: Calculated value (C ₁₅ H ₂₄ O) C; 81.76,
H; 10.98 (%) measured value C; 81.72, H; 10.8
9 (%)

[0023]

According to the method of the present invention, blue stink bugs ( Neza) are produced in one step from raw materials that are inexpensive and easily available.
You can acquire the ra and Acroternum species) of the sex pheromone.

Claims (1)

[Claims] 1. A structural formula: And an epoxy ketone represented by the general formula: [In the formula, Ph represents a phenyl group, and X represents a halogen atom. ] And a phosphonium salt represented by the following formula are reacted in the presence of a base: A method for producing a sex pheromone of a blue stink bug represented by.