JPS6033419B2 - Hydroxyester compound and tobacco flavor improver comprising the compound - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel hydroxyester compound and a tobacco flavor improver comprising the compound.

In recent years, the quality of cigarettes has rapidly shifted to so-called light-tasting products with low nicotine and low tar. Mild types with less oxidation are increasingly being used.

Also used are recycled tobacco, which is made by extracting the backbone and waste tobacco with water, and then molding the citron residue into a sheet using the papermaking method, as well as so-called artificial tobacco, which is made from plants other than leaf tobacco, or from various inorganic and organic components. This is becoming more and more common. However, such tobacco raw materials generally lack aroma, are often irritating, and lack flavor, so the development of novel aroma and taste improvers to improve these drawbacks has become an extremely important issue. The present invention was made from the above-mentioned viewpoint with the purpose of providing a new compound that is effective in improving the flavor and flavor of tamako, and the present inventors have developed a compound that is already highly evaluated as a tobacco flavoring agent. While studying a method for synthesizing 3-hydroxy-B-damascone, a new compound was discovered as a synthetic intermediate thereof, and it was also discovered that this new compound itself has a remarkable effect on improving the aroma and taste of tobacco, leading to the present invention.

That is, the present invention is a hydroxyester compound represented by the general formula (1) and a tobacco flavor improver comprising the compound. (In the formula, R represents a -C melon group or a -C2 day group.

) In the general formula (1), the compound where R=CH3 is methyl-2,6,6-trimethyl-4-hydro. xy-1-cyclohexene-1-carboxylate (hereinafter referred to as the present compound (l)
a). ), R=C2day5 is ethyl-2.
6,6-trimethyl-4-hydroxy-1-cyclohexene-1-carboxylate (hereinafter referred to as the present compound (lb)
That's what it means. ), respectively. This compound (la)
and (lb) are colorless oily substances with a strong fruit-like aroma including a wood-like aroma, and the spectral data are as shown below.

Table 1 Spectral data of the present compound (la) o Mass spectrometry (m/e) 198 (M+), 183, 16
7, 165 (base), 151, 13ku 121, 10
5, 95, $, 91o infrared absorption spectrum (arc-1)
I00, 296 2930, 1725, 1710, 16
551435, 1248, 1230, 1072, 103
8o nuclear magnetic resonance spectrum (6, trace) 1.06 (group,
s), 1.24 (group, s), 1.52 (IH, broa
d, OH), 1.67 (3 days, s), 1.35-2.4
0 (4th, m), 3,74 (group, s), 4,06 (IH
, m) Table 2 Spectral data of the present compound (lb) o Mass spectrometry (m/e) 212 (M +) 197, 194
, 179, 167, 151, 121, 107, 105
95 93 91, 81, 7977o Infrared absorption spectrum (arc-1) I 20, 2 job 0, 295 stop 1728, 1
715 168L1470, 1450, 1375, 12
50123fu 1077, 1043o nuclear magnetic resonance spectrum (8 legs) 1. Female (Chihito, s), 1. Pine (spotted, s),
1.32 (9 days, t), 1.55 (IH, s, OH),
1.70 (group, s), 1.4-2.25 (mountain, m), 4
．． 24 (ga, q), 4.06 (IH, m) Next, an example of the method for synthesizing the present compound will be explained based on the reaction process diagram of the following formula for (lb).

First, ethyl acetoacetate (0) and mesityl oxide (m)
is refluxed in the presence of a catalytic amount of zinc chloride to form ethyl-2
- Obtain 6,6-trimethyl-4-oxo-2-cyclohexene-1-carboxylate (N). (J.○rg
．． Chem. 35, 10 balls, (1970)). Next, this ketoester (W) is reacted with ethylene glycol in an amount of 1 to 2 q moss equivalents, preferably IM sonic equivalents, in benzene in the presence of a catalytic amount of para-toluenesulfonic acid to form a ketal (V). This ketal (V) is hydrolyzed at low temperature (0°C to room temperature) using a mixture of perchloric acid, water, and tetrahydrofuran, neutralized with an alkali such as sodium bicarbonate, and then an organic solvent such as ether or chloroform. Extract with . The 8 Ketoesters (W) obtained
When a mixture of Q and ketoester (W) is reacted with lithium aluminum hydride under ice cooling, a crude product of the present compound (lb) is obtained as a viscous oil, which is purified by silica gel using chloroform as a solvent. The pure compound (lb) can be obtained by column purification. Moreover, the present compound (la) can be synthesized in a similar manner by using methyl acetoacetate in place of ethyl acetoacetate.

As mentioned above, the present compounds (la) and (lb) each have a strong fruit-like aroma including a wood-like aroma, and have desirable suitability as a tobacco flavor improver.

That is, when this compound is added to tobacco raw materials with poor aroma and smoked, it not only imparts a desirable aroma to these materials, but also exhibits excellent effects such as suppressing astringency and irritation, and increasing the sense of smoke volume. The timing and means of adding this compound to chicks are not particularly limited, and like other commonly used fragrances, after dissolving it in an organic solvent such as ethanol,
Not only can it be used by adding it to shredded tobacco, but it can also be added to cigarettes, manufacturing materials such as wrapping paper, glue, filters, etc. to improve the flavor and aroma. There are also no particular restrictions on the type of tobacco to which this compound can be applied, including cigarettes made from regular leaf tobacco, pipe tobacco,
In addition to cigar cigarettes, this compound may also be used during the manufacturing process or after the product has been manufactured, such as regenerated cigarettes made from tobacco scraps, and artificial cigarettes made from natural fibers or plant tissue cultures. By adding , the flavor can be improved.

The amount of the compound to be added may be very small; 0.00001 to 0.1% (by weight), preferably 0.0001 to 0.01% (by weight) to the tobacco or tobacco manufacturing materials. It is effective and effective even in small amounts, making it economically advantageous.

Manufacturing example J. ○rg. Chem. 3F 1053 197 Ketoester (W) obtained by refluxing ethyl acetoacetate (b) and mesityl oxide (m) in the presence of zinc chloride according to the method described in Ikari (71.4 mol)
and ethylene glycol (47.4 mol, 7.65 mol)
) was refluxed in benzene (690') for 4 hours in the presence of para-toluenesulfonic acid for 0.4 hours.

The reaction proceeds under azeotropic dehydration, and after the reaction is complete, p-toluene sulfonic acid and excess ethylene glycol are shaken off with a saturated aqueous sodium bicarbonate solution, and the organic layer is purified using a Florisil column using benzene as a solvent. , about 1
8 ketals (V) containing 0% Q-ketal 12.
7 days (yield 70.0% based on ketoester (W)) was obtained. Subsequently, 12.7 hours of this ketal (V) was mixed with perchloric acid (60% aqueous solution): water: tetrahydrofuran = 2:1:
2 (volume ratio) of a solution of 120% was added to a rope at 5°C,
After hydrolysis for 2 minutes, saturated aqueous sodium bicarbonate solution 4
Neutralized with [00]. Then, the reaction solution was extracted three times with 300% ether to obtain a mixture of B-form ketoester (W) and Q-form ketoester (W) ((W):(W)=8:2
) 10.5 mmol (50.0 mmol) was obtained. Subsequently, this mixture was mixed with 0.95 liters of lithium aluminum hydride.
A solution of (25.0 mol) in anhydrous ether (80 mol)
), and after reacting for 1 hour while cooling with ice, 80 g of water was added dropwise, and the ether layer was separated. Further, the aqueous layer was extracted twice with 50 ml of ether, combined with the separated ether layer, dried over sodium sulfate, and concentrated to obtain 8.4 g of viscous oil. By further purifying this with a silica gel column using chloroform as a solvent, the present compound (lb) was obtained from 8 ketals (V) in a yield of 60.
I was able to get it at 0% (6.3 evenings). Example 1 A 0.1% by weight ethanol solution of the present compound (lb) synthesized by the method described in the above example was added to 100 shredded tobacco leaves for Japan Monopoly Corporation (trade name: "Highlight" (registered trademark)).
This compound was added to shredded tobacco at a concentration of 0.0005% by weight and rolled into paper, and the aroma, taste, and irritation when smoked were compared using a two-point discrimination method using unflavored products as a control. .

The evaluations by the 20 dedicated panels are as shown in Table 3. The numbers in Table 3 of Table 3 indicate the number of people who rated it as good.

* indicates a significant difference with a 5% risk rate. Example 2 A 0.1 wt% ethanol solution of the present compound (lb) synthesized by the method of the above production example was applied to shredded tobacco of leaf group for Japan Monopoly Corporation's product name "Cherry" (registered trademark). On the other hand, the present compound was added by spraying to a concentration of 0.008% by weight and rolled into cigarettes, and the flavor and taste when smoking these were compared using a two-point discrimination method using an unflavored product as a control.

The evaluation by 84 general panelists was as shown in Table 4. The numbers in Table 8 of Table 4 indicate the number of people who rated it as good.

* indicates a significant difference with a 5% risk rate. Example 3 Waste tobacco was extracted with a hot K of 80 qC and further divided into a water-soluble part and a water-insoluble part, and then the water-insoluble part was beaten and 15% of its dry weight of softwood kraft pulp was added. For 50 sheets of recycled cigarettes made by molding the mixture into thin paper and adding the above-mentioned water-dropping part to the thin paper,
0.1 of this compound (lb) synthesized by the method of the above production example
A wt% ethanol solution was added to sheet-shaped regenerated tobacco so that the amount of this compound was 0.003% by weight, then cut and rolled up, and the flavor was evaluated using a two-point discrimination method using a non-additive product as a control. compared.

The evaluation by the 20 expert panel members was as shown in Table 5. Table 5 [89] The numbers in the table indicate the number of people who rated it as good.

* indicates a significant difference with a 5% risk rate. Example 4 To scrap tobacco, add 8 times its weight of water and beat it through a paper refiner.
% of softwood kraft pulp was spread thinly on an iron plate and dried with 120 qo of hot air to obtain 100 pieces of recycled tobacco sheet. compound (la)
A 0.1% by weight solution of ethyl alcohol was added to sheet-shaped recycled tobacco by spraying so that the amount of this compound was 0.002% by weight, and then cut and rolled up. The aroma and taste were compared using the point discrimination method. Specialized panel 20
The evaluation by name is as shown in Table 6. Table 6 (
The numbers in the table indicate the number of people who rated it as good.

Claims (1)

[Claims] 1. A hydroxyester compound represented by general formula (I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (R in the formula represents a -CH_3 group or a -C_2H_5 group) 2. A flavor improver for tobacco comprising a hydroxyester compound represented by the general formula (I). ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (R in the formula represents -CH_3 group or -C_2H_5 group)