JPS5822090B2 - "2-(Ptenoyl or Pentenoyl)-picyclo[2,2,1]heptene derivative and its production method" - Google Patents

Description

Detailed Description of the Invention The present invention relates to the following general formula (I), (wherein R1, R2 and R3 represent a hydrogen atom or a methyl group, R4 represents a methyl group or an ethyl group, and the dotted line bond is The present invention relates to a novel 2-(butenoyl or pentenoyl)-bicyclo(2,2,1]heptene derivative represented by the following formula (present or absent) and a method for producing the same.

The compound represented by the following general formula (n) (wherein R1, R2 and R3 have the above meanings), which is a conventionally known raw material of the present invention, has a very unpleasant strong odor. The novel compound represented by formula (I) of the present invention has a flower-like or grass-like odor, although it has a strong odor.

They found that it is useful as a fragrance and completed the present invention.

According to the present invention, the 2-(butenoyl or pentenoyl)-bicyclo(2,2,1)heptene derivative of the present invention is produced by the method shown in the following reaction formula.

(In the formula, R,, R2, R3, R4 and the dotted line have the above-mentioned meanings.) That is, the compound of formula (■) is reacted with acetaldehyde or propylaldehyde in the presence of a condensing agent in an inert solvent to form a β-hydroxyketone. 2-(butenoyl or pentenoyl)-visychloro[2,2,1]heptene derivative C
I) is produced.

The raw material compound (II) of the present invention is obtained by subjecting cyclopentadiene, which is industrially available at low cost, to a Deels-Alder reaction with an α, β-, β-carbonyl compound to form a bond as shown in the dotted line in (II)E. It is easily produced by preparing a compound and subjecting it to catalytic reduction by a conventional method to obtain a compound in which the dotted line bond in the formula (n) is not present.

These α,β-unsaturated unsaturated nylbonyl compounds include methyl vinyl ketone, 3-penten-2-one, 4-hexene-
Examples include 3-one, mesityl oxide, and the like.

The reaction between the compound of formula (II) and acetaldehyde or propylaldehyde is preferably carried out in the presence of a condensing agent such as lithium diisopropylamine or N-methylaniline magnesium bromide in an inert solvent such as ether, tetrahydrofuran or hexane. .

The reaction temperature is preferably -70 to -20°C, particularly -70 to -30°C.

The β-hydroxyketone compound thus obtained ([D] in an aprotic solvent such as methylene chloride, dichloroethane, benzene, ether, tetrahydrofuran, hexane, etc. in the presence of a mineral acid or a Lewis acid)
A dehydration reaction at °C yields the desired product of formula (I).

In particular, the dehydration reaction is carried out in the presence of para-toluenesulfonic acid for 30~
Good results are obtained by performing the process at a temperature of 60°C.

Next, reference examples and examples will be given and explained.

Reference Example 1 5 g of stannic chloride and 100 mA of methylene chloride were placed in a 500 m 110 four-necked reaction flask equipped with a thermometer, calcium chloride drying tube, dropping funnel, and stirring device, and heated to 20°C while stirring under a nitrogen stream. Cooling.

Thereto, 98 g of mesityl oxide was slowly added dropwise, and then 158 g of cyclopentadiene was added dropwise.

After the completion of the dropwise addition, the mixture was stirred at -10 to -5° C. for 5 hours, and then the reaction mixture was poured into iced hydrochloric acid and extracted with methylene chloride.

The extract is washed with water, neutralized with a saturated aqueous sodium bicarbonate solution, and dried with Glauber's salt after washing with water.

The residual oil after distilling off methylene chloride is distilled under reduced pressure, and the boiling point is 55-6.
Fraction 46.6.9 is obtained at 0° C. and 15 mmHg.

This product was confirmed to be 2-acetel-3,3-dimethylbicyclo(2,2,1)hebutene-5 from the analysis results by mass spectrum, IR, and *yxR spectrum.

The theoretical yield is 34.3%. IR2 1 700
, 1 1 60, 730 cm 'MS:
m/e 164 (M”), 149.99 (BP)
, 66°
ΔNMR: 0.8 (3H,s), 1.4 (3H
,s), 2.0 (3H,s), 0.58-0.6
4ppm (2H, m).

Reference Example 2 Using the same reaction apparatus and reaction conditions as Reference Example 1, 84 g of 3-penten-2-one and 100 g of cyclopentadiene were added dropwise.

After completion of the dropwise addition, the reaction mixture was stirred for 1 hour at 0 to 5 DEG C. and then placed in iced hydrochloric acid.

Thereafter, the procedure was carried out in the same manner as in Reference Example 1, and the residual oil after distilling off the methylene chloride was distilled under reduced pressure at 75-78°C and 110 mmH.
110.1 g of a 9cl') fraction are obtained.

This is MS. NMR, IR spectrum analysis results 2-acetel-3-methylbicyclo(2,2,1]hebutene-
It was confirmed that it was 5.

The theoretical yield is 74.096.

・9IR:
1700, 1160, 1170, 710°.

-1M5: m/e150 (M+), 107, 85
, 66 (BP) NMR: 1.15 (3H,d), 2.0 (3H
, s), 5.8 to 6.3 ppm (2H, m) Reference Example 3 85 g of methyl vinyl ketone was placed in a 500 ml four-necked reaction flask equipped with a thermometer, reflux condenser, dropping funnel, and stirring device. , add ether 100rtJ, 1
While keeping the temperature around 0℃ and stirring, add cyclopentadiene 9.
A mixed solution of 0 g and 100 ml of ether is added dropwise.

After the dropwise addition is complete, the temperature is gradually returned to room temperature, and the mixture is further heated until the ether gently refluxes.

Once reflux begins, stop heating and continue stirring overnight.

Next, the ether is recovered and the residual oil is distilled under reduced pressure, resulting in a boiling point of 7.
5-78°C/12mmH9 fraction 153. : Get l.

This thing is IR. From the results of MS and NMR spectrum analysis, it was confirmed that it was 2-acetylbicyclo[2,2,11butene-5.

The theoretical yield is 93.1%.

IR: 1700, 1160, 1180, 730°710
cm' MS: m/e136 (M"), 93, 71, 6
6 (BP).

NMR: 2.0 (3H, s), 5.7-6.2
ppm (2H, m).

Example 1 300ml set with thermometer, calcium chloride drying tube, dropping funnel and stirring device! 15 g of diisoglopylamine and 100 ml of dry tetrahydrofuran (THF) were placed in a four-necked reaction flask, and the mixture was cooled to -70° C. with stirring under a nitrogen stream.

Here, 70ml of a 15th hexane solution of n-butyllithium is added.
1 dropwise, then 2-acetelium 3. ．． 3-dimethylbicyclo[2,2,1]hept-5-ene 16.4 [THF20? ? A mixed solution of Zl is added dropwise.

After completion of the dropwise addition, the temperature was returned to -25°C, stirred for 1.5 hours, and cooled again to -70°C.

8g of acetaldehyde and 10 THF here? ? A mixed solution of Z/ is added dropwise.

The reaction mixture was slowly returned to room temperature over about 3 hours, poured into ice-cold hydrochloric acid, and extracted with ether.

The ether layer was washed with water, neutralized, and dried with sodium sulfate.

Residual oil after ether distillation 19,2,! Dissolve 7 in 150 ml of methylene chloride, and add 1 ml of p-toluenesulfonic acid to this.
．． Add 5 g and heat under reflux for 3 hours.

The reaction mixture was neutralized, washed with water, and dried with sodium sulfate solution in methylene chloride.

The residual oil after methylene chloride recovery is distilled under reduced pressure, and the boiling point is 78-8.
9.5 g of fraction 09C/1imH,9 is obtained.

According to the results of IR, MS, and NMR spectroscopy, this product is 2-(2-butenoyl)-3,3-dimethylbicyclo(
It was confirmed to be 2,2,1]hept-5-ene.

The theoretical yield is 50.0.

-IR: 1695, 1665, 1630, 97
0°710cm.

MS: m/e190 (M+), 175.147°125
(BP), 109,69,66°NMR: 0.73 (3H, s), 1.4 (3H,
s), 1.9 (3H, d), 5.8-7.1 pp
rn(4H,m) This product has a flower-like aroma.

Example 2 Diimpropylamine lithium was prepared using the same reaction apparatus and reaction conditions as in Example 1, and 3-methyl-2-glopionylbicyclo(2,2,11hept-5-r-7
16,49 and THF 20m12 (7) mixed.

Add the combined solution dropwise.

After completion of the dropwise addition, the temperature was returned to -25°C, stirred for 1.5 hours, and then cooled to -70°C again.

A mixed solution of 8 g of acetaldehyde and THFlomA was added dropwise thereto.

After the dropwise addition was completed, the temperature was gradually returned to room temperature, and the reaction mixture was poured into iced hydrochloric acid and diluted with ether.

Extract.

The ether layer was neutralized, washed with water, and then dried with sodium sulfate.

Residual oil after ether distillation 23. , l'Bensen 150m
/, add 1.5 g of p-toluenesulfonic acid,
Warm to 50°C while stirring.

After 3 hours, the reaction solution was neutralized, washed with water, and then washed with benzene. 21.1g of residual oil was distilled under reduced pressure to a boiling point of 98℃/3mmH.
11.1 g of g(y) fraction are obtained.

This is the result of IR, MS, NMR spectrum analysis 2
It was confirmed that -(2-methyl-2-butenoyl)-3-methylbicyclo(2,2,1) to 7')-5-ene:.

The theoretical yield is 58.4%.

IR:1660,1230,710Crn 0MS
: m/e190 (M+), 175, 125 (B
P), 83.69.66.55°NMR: 1.12 (3H,d), 1.78 (3
H, d).

1.95 (3H, s 'l, 5.6-6.3 (2H.

m), 6.73 ppm (IH,q).

This product has a floral aroma.

Example 3 A diisopropylamine lithium solution is prepared by adding diisopropylamine IL9 to 100 mAK of dry tetrahydrofuran (THF) and 70 ml of n-butyllithium at -60°C.

Then, at the same temperature, 16.6.9 2-acetelium 3.3-
30ml of dimethylbicyclo[2,2,1)heptane!
of dry THF and added dropwise to diisopropylamine lithium solution.

After the reaction solution is once returned to room temperature, it is cooled again to -60°C.

Add 6.6g of acetaldehyde to this in 20ml. A solution dissolved in dry THF was added dropwise over a period of 2 hours while maintaining the temperature at -60°C.

Then, the reaction mixture was returned to room temperature and stirred for 1 hour.
The mixture was poured into iced dilute hydrochloric acid and extracted with ether.

The ether layer was washed with water, dried with Glauber's salt, and the ether was distilled off to obtain 21.0 g of an oily substance.

This oil was dissolved in dichloroethane at 160 mA and
g of p-toluenesulfonic acid was added thereto, and the mixture was heated under reflux for 2 hours to perform dehydration.

The dichloroethane layer was washed with a quaternary sodium carbonate aqueous solution, washed with water, dried over anhydrous magnesium sulfate, and the solvent was distilled off.
12.3 g of oil was obtained.

This is vacuum distilled and has a flower-like aroma with a boiling point of 72 to 73 degrees.
C/1 mwHg colorless oil 10.69 (yield 64.3
%) was obtained.

This is 2-(2-
It was confirmed that the product was 3,3-dimethylbicyclo(2,2°1)butane.

IR: 1690.965Crr1.

MS: m/e 192 (M+), 177°NMR
:0.74 (3H,s), 1.5 (3H,8), +
9(3H,d), 6.1 (t(, J=16.0'j
, 6.8 (H, dXq, J=16, 7Hz)
Examples 4 to 8 Compounds having the aroma shown in Table 1 were obtained in the same manner as in Example 1 or 2.

Examples 9 to 14 Compounds having aromas shown in Table 2 were obtained in the same manner as in Example 3.

Claims (1)

[Claims] 1. The following general formula (wherein R1, R2 and R4 represent a hydrogen atom or a methyl group, R4 represents a methyl group or an ethyl group, and the dotted line bond is present or absent) 2-(butenoyl or pentenoyl)- represented by '
Bicyclo(2,2,1)heptene derivative. 2. Acetaldehyde or propylaldehyde is added to a compound represented by the general formula (wherein R1, R2, and R3 represent a hydrogen atom or a methyl group, and a single dotted bond is present or absent) in the presence of a condensing agent in an inert solvent. The following reaction was carried out and the general formula (wherein R4 represents a methyl group or an ethyl group, R1,
R2, R3 and the dotted line have the above-mentioned meanings), which is then subjected to a dehydration reaction. 2-(butenoyl or pentenoyl)- with the meaning given above)
A method for producing a bicyclo(2,2,1)heptene derivative. 3. The production method according to claim 2, wherein the inert solvent is ether, tetrahydrofuran or hexane, and the condensing agent is diisopropylamine lithium or N-methylaniline magnesium bromide. 4. The production method according to claim 2, wherein the dehydration reaction is carried out in an aprotic solvent in the presence of a mineral acid or a Lewis acid. 5. The production method according to claim 4, wherein the aprotic solvent is methylene chloride, dichloroethane, benzene, ether, tetrahydrofuran or hexane.