JPH0118888B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for selectively producing alkylidene norbornanol and its derivatives from alkylidene norbornene.

Conventionally known methods for producing alkylidene norbornanol from alkylidene norbornene include hydration using a mineral acid such as sulfuric acid, or organic This is a method in which acid is added to ethylidenenorbornene and then hydrolyzed.

However, in the above method, the formation of a tricyclene compound, which is a tricyclic compound, is unavoidable, which in turn reduces the selectivity of ethylidene norbornanol.

More importantly, the produced tricyclene compounds have no aroma and are far less useful as fragrances than ethylidene norbornanol, and due to the loss of the ethylidene group, they have no value as synthetic intermediates. is low. Therefore,
It cannot be said that it is a good method to obtain alkylidene norbornanol, which is the object of the present invention, by the method that involves acid addition and hydrolysis as described above.

Even if they are produced by the method described in the above publication, ethylidenenorbornanol and tricyclene compounds have the same molecular weight,
Separation is not easy using normal distillation operations. Therefore, it is economically disadvantageous to separate and remove tricyclene compounds from such reaction products in order to increase their usefulness as fragrances, and the separated tricyclene compounds
Since there is no particularly useful use, the method of the above publication is not preferred.

Furthermore, other methods for synthesizing ethylidenenorbornanol from ethylidenenorbornene are described in Canadian Journal of Chemistry, 49 ,
1142 (1971) or the so-called oxymer cure. However, in the former method, priority is given to epoxidation of the ethylidene group, so the yield of ethylidenenorbornanol is low, and in the latter method, tricyclene, which is less useful as a perfume, is produced, and neither method is satisfactory.

Therefore, the present inventors utilized the so-called hydroboration-oxidation reaction to synthesize alkylidene norbornanol from alkylidene norbornene, for example, ethylidene norbornanol from ethylidene norbornene, and produced a high The present invention was completed as a result of studying a method for obtaining alkylidene norbornanol with high selectivity.

That is, the present invention is a method for selectively producing alkylidene norbornanol, which is characterized by reacting alkylidene norbornene with diborane or a substituted borohydride compound represented by the following general formula, followed by oxidation and hydrolysis.

general formula Here, X and Y represent either a hydrogen atom, a hydrocarbon residue, or a halogen atom.

The alkylidene group of the alkylidene norbornene used in the present invention is a _C1 - _C3 alkylidene group, such as methylene, ethylidene, propylidene, isopropylidene group, etc. Among these, ethylidenenorbornene (5-ethylidene-bicyclo[2,2,1]hept-2-ene) is produced inexpensively and in large quantities as a third copolymer component for vulcanization of EP rubber, and is also produced from this raw material. 5-ethylidene-2 obtained by the method of the present invention
and/or 3-norbornanol is highly useful as a fragrance.

In the method of the present invention, first, diborane or a substituted borohydride compound represented by the above general formula is reacted with alkylidene norbornene.

Next, as the substituted borohydride compound of the above formula, for example, dicyamylborane, dicyclohexylborane, thexylborane, diisopinocampheylborane, 9-borabicyclo[3,3,1]
nonane, mono- or di-ethylidenenorbornylborane, or mono- or dichloroborane.

To carry out the method of the present invention, diborane may be used in an amount of 0.1 to 1.0 mol, and in the case of a substituted borohydride compound, 0.5 to 2.0 mol may be used per mol of ethylidene norbornene.

This reaction is usually carried out in a solvent, which includes:
At least one or a mixture of two or more selected from tetrahydrofuran, ethyl ether, methyl ether, isopropyl ether, mono- or diethylene glycol dimethyl ether, dioxane, dioxolane, and acetal can be used.

The reaction temperature is -60 to 230°C, preferably -40 to 60°C.
℃, and the lower the reaction temperature, the higher the selectivity of the positions described below, but the reaction tends to be slower. The reaction pressure is normal pressure, but may be slightly reduced or increased.

The reaction is usually carried out for 0.5 to 5 hours, and the reaction products are oxidized and hydrolyzed, usually without separation.

For oxidation, hydrogen peroxide, organic peroxide, amine oxide, molecular oxygen, etc. are used. When using hydrogen peroxide or an organic peroxide, following the reaction with a borane compound, hydrogen peroxide or organic peroxide is mixed with an aqueous solution of sodium hydroxide or with tetrahydrofuran, dimethylene glycol dimethyl ether or ethyl alcohol. Oxidation is carried out by adding the liquid to the reaction solution. For oxidation using amine oxide, an amine oxide-benzene solution is used, followed by hydrolysis with an acidic aqueous solution of sulfuric acid. When using molecular oxygen, anhydrous conditions, such as anhydrous n-heptane,
It is oxidized by bubbling oxygen or air in benzene, and then hydrolyzed with an aqueous sodium hydroxide solution. The oxidation reaction temperature is 0 to 80°C, preferably 5 to 80°C.
It is 50℃.

In the above reaction, a hydrolysis reaction occurs simultaneously with or subsequent to the oxidation. This hydrolysis reaction proceeds in acidic, neutral or alkaline conditions, and alkylidene norbornanol is eventually synthesized with good selectivity.

After the reaction is completed, the solvent is distilled off, and alkylidene norbornanol can be easily obtained in high purity by a usual economical and easy separation means such as distillation.

As described above, the method of the present invention can be easily carried out, but to summarize the characteristics of the method of the present invention, alkylidene groups such as ethylidene groups are not easily changed by reactions, and isomerization reactions are not involved. Since the reaction is small, tricyclene compounds are not produced, and therefore, according to the method of the present invention, the target product can be used as a fragrance ingredient simply by ordinary distillation and purification without complicated separation or purification. You can get it.

The alkylidenenorbornanol produced by the method of the present invention has positional isomers and stereoisomers due to the hydroxyl group. Therefore, if ethylidene norbornene is taken as an example of alkylidene norbornene, ethylidene norbornene 2- or 3-norbornanol is produced. However, 5-ethylidene-2-norbornanol predominates, usually about 70% of the alcohol obtained.

Furthermore, since a hydrogen atom is also bonded to the norbornane ring carbon atom to which the hydroxyl group is attached, endo- and exo-stereoisomers may exist as shown in the formula below, but the exo-isomer accounts for 90% or more. However, the oxidation and hydrolysis using molecular oxygen described above slightly increases the amount of endo isomers.

That is, in the method of the present invention, exo-5-ethylidene-2-norbornanol is mainly produced.

Esterification in the present invention is carried out between the alkylidene norbornanol obtained as described above and C ₁ -
This is carried out by reacting a C ₆ aliphatic carboxylic acid or an aromatic carboxylic acid, an acid anhydride or acid chloride thereof, in the presence or absence of a catalyst, by a conventional method.

_C1 - _C6 aliphatic carboxylic acids include formic acid, acetic acid,
These include propionic acid, butyric acid, isobutyric acid, valeric acid or isovaleric acid. In addition, aromatic carboxylic acids are
These include benzoic acid, phenylacetic acid, cinnamic acid, anthranilic acid or salicylic acid.

In addition, in this esterification, the ratio of the positional isomer and the stereoisomer of the endo or exo isomer due to the hydroxyl group of alkylidenenorbornanol, which is the raw material, hardly changes.

Here, examples of esters obtained by the above esterification include esters obtained from 5-ethylidene-2 and 3-norbornanol.
It will look like this:

That is, acetic acid (5-ethylidene-2- and 3-norbornyl) ester, propionic acid (5-ethylidene-2- and 3-norbornyl) ester,
-ethylidene-2 and 3-norbornyl) ester, isobutyric acid (5-ethylidene-2 and 3-
norbornyl) ester, butyric acid (5-ethylidene-2 and 3-norbornyl) ester, pivalic acid (5-ethylidene-2 and 3-norbornyl) ester, formic acid (5-ethylidene-2 and 3-norbornyl) ester, benzoic acid (5-ethylidene-2 and 3-norbornyl) ester,
Phenylacetic acid (5-ethylidene-2 and 3-norbornyl) ester, cinnamic acid (5-ethylidene-2 and 3-norbornyl) ester, anthranilic acid (5-ethylidene-2 and 3-norbornyl) ester, salicylic acid (5- ethylidene-2 and 3-norbornyl) esters.

Further, in the oxidation to obtain a ketone from an alcohol in the present invention, the alkylidene norbornanol obtained as described above is oxidized in a liquid phase at -20 to +130°C, preferably 0 to 110°C.

It has been found that side reactions occur when the reaction temperature is lower than -20°C and the reaction is carried out for a long time with a strong oxidizing agent, or when the reaction temperature is set above 130°C and oxidation is carried out rapidly. Side reactions include changes in the alkylidene group and cleavage of the norbornene ring, and when these occur, the yield decreases and the quality of the target product cannot be guaranteed. For this reaction, a solvent that is stable against oxidation, such as water, acetic acid, ketone, pyridine, benzene, toluene, etc., should be selected, and the reaction can be carried out in any of the following formats: water dispersion system, water emulsion system, or complete solution system. It is carried out with The type of oxidizing agent should be selected taking into account the solvent, and includes chromic acid, permanganate, nitric acid, ozone, manganese dioxide-sulfuric acid, chlorine water, hydrogen peroxide, peroxide, ferric salts, peroxide, etc. Halogenates, oxygen, cyclohexane, acetone, dicyclohexylcarbodiimide-dimethylsulfoxide, and the like are used in the presence or absence of a catalyst.

Next, in order to further explain the technical content of the present invention, examples will be shown below. However, the following examples are extracted from a large number of experimental examples, and the present invention is not limited to the following examples. should not be construed as
It goes without saying that the embodiments may be modified and implemented as desired without departing from the spirit and spirit of the present invention.

Example 1 Synthesis of 5-ethylidene-2 and 3-norbornanol 36.0 g of 5-ethylidene-2-norbornene
(0.300 mol) in 250 ml of dry tetrahydrofuran, then 5.0 g of sodium borohydride.
(0.129 mol) was added. Boron trifluoride ether complex salt 14.0 ml (0.111 mol) was added while cooling the mixture on ice.
was added dropwise over a period of about 0 minutes. 10-20 minutes after completion of dripping
The mixture was stirred at ℃ for about 2 hours. While cooling the reaction mixture on ice, add 25.2 ml of water, then 34.1 ml of 3N aqueous sodium hydroxide solution, and then add 30% hydrogen peroxide solution.
34.1 ml was gradually added dropwise. After stirring the reaction mixture at about 50°C for 2 hours, a benzene-ether mixture was added.
The mixture was poured into 100 ml of water, washed several times with a small amount of saturated brine, and the organic layer was dried over anhydrous magnesium sulfate.
After distilling off the solvent, the residue was distilled under reduced pressure to obtain 24.8 g of colorless 5-ethylidene-2 or 3-norbornanol (yield:
60%; bp, 60-61°C/0.45mmHg).

ir (neat method): ~3300cm ^-1 (O-H stretching vibration), ~1680cm ^-1 (C=C stretching vibration of ethylidene group), 1060-1080cm ^-1 (C-O stretching vibration of alcohol).

nmr (CDCl ₃ ): 4.5-5.0τ (multiplet, 1H), 6.0-6.3τ (multiplet, 1H), 6.7τ (singlet, 1H), 7.2τ (broad singlet, 1H), 7.5-7.7 τ (multiplet, 1H), 8.4τ (singlet, 3H), 7.9~8.9τ (multiplet, 6H).

Elemental analysis (as C ₉ H ₁₄ O) C (%) H (%) Calculated value 78.3 1.0 Actual value 77.6 1.1 In addition, analysis by gas chromatography revealed that 95% of the alcohol content obtained was exo isomer, and 5 -Ethylidene-2-norbornanol is 65
It was %. Further, no tricyclene-based compounds were contained at all.

Example 2 Synthesis of 5-ethylidene-2 and 3-norbornanol In Example 1, boron trifluoride ether complex salt was added dropwise while cooling to -40 to -30°C, and after the dropwise addition was completed, the mixture was stirred at -20°C for 5 hours. The reaction was carried out in the same manner as in Example 1, and 33.1 g (yield, 80%) of colorless 5-ethylidene-2 or 3-norbornanol having the same odor as that of Example 1 was obtained. According to analysis, 5-ethylidene-2-norbornanol was 75%.

Example 3 Synthesis of 5-ethylidene-2-norbornanol In a 300 ml flask, add 9-borabicyclo[3,
3,1] Add 24.4 g (0.200 mol) of nonane and 40 ml of dry tetrahydrofuran, and add 5-
A solution of 24.0 g (0.200 mol) of ethylidene norbornene in 20 ml of dry tetrahydrofuran was added dropwise, and the mixture was heated under reflux for about 1 hour. Add 20 ml of water and 65 ml of 3N sodium hydroxide aqueous solution to the reaction mixture at room temperature, and further dilute to 30% while keeping the temperature below 40°C.
65 ml of hydrogen peroxide solution was gradually added dropwise.

The reaction mixture was stirred at 40°C for about 1 hour, then extracted with ether, and the extract was dried and distilled under reduced pressure to obtain a colorless 5 with an odor similar to that of Example 1.
37.3 g (yield, ~90%) of -ethylidene-2-norbornanol was obtained.

Example 4 Synthesis of 5-isopropylidene-2-norbornanol Sufficiently purified dicyclohexylborane (0.200 mol of cyclohexene and 0.100 mol of borane-tetrahydrofuran complex were mixed with 50 mol of dry tetrahydrofuran)
(obtained by reacting in ml) 0.100
13.4g of 5-isopropylidenenorbornene per mole
(0.100 mol) was added at 0-5°C. reaction mixture
After stirring at below 20℃ for about 2 hours, add 10ml of water, 3N.
Add 35 ml of sodium hydroxide aqueous solution and further at 40°C.
35 ml of 30% hydrogen peroxide solution was gradually added dropwise.
After stirring for 1 hour, extraction with ether, drying the extract and distillation under reduced pressure yields colorless 5-isopropylidene with a vetiver-tinged hexanol odor.
2-Norbornanol 13.7g (90% yield, bp62
~63°C/0.30mmHg).

ir (neat method): ~3300cm ^-1 (O-H stretching vibration), ~1675cm ^-1 (C=C stretching vibration of isopropylidene group), 1060-1080cm ^-1 (C-O stretching vibration of alcohol).

nmr (CDCl ₃ ) 6.1~6.3τ (multiplet, 1H), 6.7τ (singlet, 1H), 7.3τ (broad singlet, 1H), 7.6~7.7τ (multiplet, 1H), 8.3τ (singlet line, 3H), 8.4τ (singlet, 3H), 8.0~8.9τ (multiplet, 6H).

As elemental analysis (C ₁₀ H ₁₆ O) C(%) H(%) Calculated value 78.95 10.53 Actual value 78.55 10.81 Example 5 Synthesis of acetic acid (5-ethylidene-2 and 3-norbornyl) ester Obtained in Example 1 After 5.0 g (0.036 mol) of 5-ethylidene-2 and 3-norbornanol were dissolved in 50 ml of dry pyridine, 3.1 ml (0.044 mol) of acetyl chloride was gradually added dropwise while cooling with ice.
After the addition was complete, the reaction mixture was stirred at 0-10°C overnight. The reaction mixture was poured into 100 ml of water, and then extracted with a benzene-ether mixture. The separated organic layer was washed twice with diluted hydrochloric acid, further washed twice with water, and then dried over anhydrous magnesium sulfate. After distilling off the solvent, distillation under reduced pressure yields the colorless title compound,
Acetic acid (5-ethylidene-2 and 3-norbonyl) ester 5.3 g (yield, 82%; bp, 53°C/
0.15 mmHg).

ir (neat method) ~1735cm ^-1 (Stretching vibration of C=O) ~1685cm ^-1 (C=C stretching vibration of ethylidene group) 1240 and 1230cm ^-1 (C-O-C stretching vibration of ester) O-H The stretching vibration (~3400cm ^-1 ) disappears by esterification.

nmr (CDCl ₃ ): 4.4~4.9τ (multiplet, 1H), 5.2~5.5τ (multiplet, 1H), 7.1τ (broad singlet, 1H), 7.5~7.6τ (multiplet, 1H), 8.0 τ (singlet, 3H), 8.4τ (singlet, 3H), 7.9~8.7τ (multiplet, 6H).

In addition, gas chromatography analysis (column packing material: silicone SE-30, column length: 0.25φ x 90
According to the column (made of stainless steel, column temperature 90°C), it was found that acetic acid (5-ethylidene-2-norbornyl) ester was the main component, and 95% was exo-isomer.

And this one had a woody scent with an ester-like vetiver tone.

Example 6 Propionic acid (5-ethylidene-2 and 3-
Synthesis of (norbornyl) ester Esterification was carried out in the same manner as in Example 5, except that propionyl chloride was used instead of acetyl chloride, and 5.3 g of the title compound (yield, 70
%; bp58-62°C/ _0.3mmHg ; ^n20D , 1.4728).

The structure was determined from the IR spectrum (neat method) showing a strong absorption band at 1739 cm ^-1 characteristic of carbonyl absorption and the broad absorption band around 1190 cm ^-1 of propionate, and from the nmr spectrum (CDCl ₃ ).

And this one had a woody scent with a slightly fruity vetiver tone.

Example 7 Synthesis of isobutyric acid (5-ethylidene-2 and 3-norbonyl) ester In Example 5, instead of acetyl chloride,
Esterification was carried out in the same manner except that isobutyric acid chloride was used, yielding 5.1 g of the title compound (yield: 68
%; bp, 63-65°C/0.6 mmHg; n ²⁰ _D , 1.4650).

The structure was determined from the IR spectrum (neat method) showing a strong absorption at 1748 cm ^-1 characteristic of carbonyl absorption and a broad doublet at 1200 cm ^-1 and 1160 cm ^-1 of isobutyrate, and from nmr (CDCl ₃ ). .

And this one had a woody scent with a slightly fruity vetiver tone.

Example 8 Synthesis of butyric acid (5-ethylidene-2 and 3-norbornyl) ester In Example 5, instead of acetyl chloride,
Esterification was carried out in the same manner except that butyric acid chloride was used to obtain 5.4 g of the title compound (yield, 71%; b.
p., 73° C./0.5 mmHg; n ²⁰ _D , 1.4701).

IR spectrum is 1730cm characteristic of carbonyl
The structure was determined from the strong absorption at ^-1 and broad absorption in the 1180 cm ^-1 region of butyrate, and from the nmr spectrum (CDCl ₃ ).

This one had a slightly fruity, vetiver-tinged, woody scent.

Example 9 Synthesis of pivalic acid (5-ethylidene-2 and 3-norbornyl) ester In Example 5, instead of acetyl chloride,
Esterification was carried out in the same manner except that pivaloyl chloride was used to obtain 5.7 g of the title compound (yield, 71%;
bp, 67-69°C/0.5 mmHg; n ²⁰ _D , 1.4643).

IR spectrum is 1724cm ^-1 due to carbonyl absorption
The structure was determined from the strong absorption of pivalate and broad absorption in the 1150 cm ^-1 region of pivalate, and from the nmr spectrum (CDCl ₃ ).

And this one had a woody scent with a slightly fruity vetiver tone.

Example 10 Synthesis of formic acid (5-ethylidene-2 and 3-norbornyl) ester 0.96 g (0.040 mol) of sodium hydride was added to 60 ml of dry tetrahydrofuran, and the 5-ethylidene obtained in Example 1 was added to the suspension. 2 and 3
- 5.00 g (0.036 mol) of norbornanol was added dropwise at room temperature. While stirring this mixture at -10°C, 3.00 g (0.041 mol) of ethyl formate was added dropwise, and the mixture was reacted at -10°C for about 4 hours and then at 25°C for about 72 hours. Pour the reaction mixture into 50 ml of ice water,
After extraction with a benzene-ether mixture and washing the extract with water, drying over anhydrous sodium sulfate and subsequent distillation under reduced pressure, 4.2 g of the title compound was obtained.
(Yield, 70%; bp, 69-71°C/6 mmHg; n ²⁰ _D ,
1.4711) was obtained.

The IR spectrum (neat method) shows a strong absorption at 1724 cm ^-1 , which is characteristic of carbonyl, and a strong absorption of formate.
exhibiting a broad absorption band of 1176 cm ^-1 and nmr
The structure was determined from the spectrum (CDCl ₃ ).

And this one had a woody scent with an ethereal vetiver undertone.

Example 11 Synthesis of benzoic acid (5-ethylidene-2 and 3-norbonyl) ester Esterification was carried out in the same manner as in Example 5, except that benzoyl chloride was used instead of acetyl chloride.

The obtained crude product was dissolved in acetone, decolorized and purified using activated carbon, and the filtrate was concentrated to yield 7.0 g of the title compound as a colorless viscous oil.
(yield 80%).

The structure was determined by IR (neat method) and nmr (CDCl ₃ ) spectra.

And this one had a woody scent with balsam-like vetiver undertones.

Example 12 Phenyl acetic acid (5-ethylidene-2 and 3-
Synthesis of Norbornyl Ester Esterification was carried out in the same manner as in Example 5, except that phenyl acetate chloride was used instead of acetyl chloride. The crude product obtained by conventional methods was purified in a manner similar to that shown in Example 11, and the title compound was obtained as a colorless viscous oil.
7.2g (yield 78%) was obtained.

This compound is ir (neat method) and nmr ( _CDCl3 )
The structure was determined by spectra.

And this one had a woody scent with musky vetiver undertones.

Example 13 Synthesis of cinnamic acid (5-ethylidene-2 and 3-norbornyl) ester Esterification was carried out in the same manner as in Example 5, except that cinnamic acid chloride was used instead of acetyl chloride. The crude product obtained in a conventional manner was purified in a manner similar to that shown in Example 11, yielding 8.3 g of the title compound as a colorless viscous oil.
(yield 85%) was obtained.

This compound is ir (neat method) and nmr ( _CDCl3 )
The structure was determined by spectra.

And this one had a woody scent with a floral vetiver tone.

Example 14 Anthranilic acid (5-ethylidene-2 and 3
-Norbornyl) ester synthesis 5-ethylidene-2 and 3- obtained in Example 1
5.0 g (0.036 mol) of norbornanol, 6.5 g (0.040 mol) of isatoic anhydride, and 0.1 g of Triton-B were dissolved in 50 ml of dimethylformamide, and the mixture was heated under reflux for 3 hours. The reaction mixture was neutralized with anhydrous sodium carbonate, washed several times with water, dried, and then dimethylformamide was distilled off. The crude product thus obtained was purified in a manner similar to that shown in Example 11 to yield 6.1 g (65% yield) of the title compound as a colorless viscous oil.

This compound is ir (neat method) and nmr ( _CDCl3 )
The structure was determined by spectra.

And this one had a woody scent with a floral vetiver tone.

Example 15 Synthesis of salicylic acid (5-ethylidene-2 and 3-norbornyl) ester 5-ethylidene-2 or 3- obtained in Example 1
Norbornanol 5.0g (0.036mol), Methyl salicylate 5.5g (0.036mol), Hydroquinone 0.2
g and paratoluenesulfonic acid 0.1g to toluene 150
After heating and boiling the mixture dissolved in ml,
The methanol produced was removed as an azeotrope with toluene. The reaction mixture was neutralized with sodium carbonate and then extracted with benzene. After washing the extract with water and drying, the volatile solvent was distilled off. The residue was dissolved in a mixture of petroleum ether and ethyl acetate (4:1) and separated and purified using a column packed with activated alumina, yielding 7.3 g of the title compound as a colorless viscous oil (yield 78%). )was gotten.

This compound has an IR spectrum (neat method) and
The structure was determined by nmr (CDCl ₃ ) spectrum.

And this one had a woody scent with a floral vetiver tone.

Example 16 Synthesis of 5-ethylidene-2 and 3-norbornanone 5-ethylidene-2 and 3- obtained in Example 1
Norbornanol 5.0g (0.036mol), parabenzoquinone 19.6g (0.181mol) in dry toluene 160g
ml, 3.7 g (0.018 mol) of aluminum isopropoxide was gradually added while stirring at room temperature. After the reaction mixture was heated under reflux for 1 hour, 100 ml of a saturated potassium sodium tartrate solution was added, and the mixture was extracted with a benzene-ether mixture. The extract was washed with a saturated sodium bicarbonate solution and twice with water, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain 4.2 g of the title compounds, 5-ethylidene-2 and 3-norbornanone (yield: 85
%; bp, 59-61°C/1.8mmHg).

ir (neat method) 1760 cm ^-1 (>c=O stretching vibration) ~1685 cm ^-1 (C=C stretching vibration of ethylidene group) O-H stretching vibration (~3400 cm ^-1 ) disappears by oxidation.

nmr ( _CDCl3 ): 4.4-4.7τ (multiplet, 0.6H), 8.0-8.4τ (multiplet, 8H), 8.8-9.2τ (quadruplet, 3H).

n ¹⁵ _D : 1.4804 Elemental analysis (as C ₉ H ₁₂ O) C (%) H (%) Calculated value 79.41 8.82 Actual value 79.05 8.60 Furthermore, gas chromatographic analysis revealed that 5-ethylidene-2-norbornanone was the main component. It was also found that 95% of the cells were exo-bodies.

And this thing had a vetiver-like hexanone smell.

Claims (1)

[Claims] 1 Alkylidene norbornene with diborane or the following general formula [In the formula, X and Y represent either a hydrogen atom, a hydrocarbon residue, or a halogen atom.] Selective production method of bornanol. 2 The alkylidene norbornene is 5-ethylidene-2-norbornene, and the alkylidene norbornanol is 5-ethylidene-2- or 3-ethylidene-2-norbornene.
- The manufacturing method according to claim 1, which is norbornanol.