Amber aroma compound and preparation method thereof

Abstract

The invention relates to the technical field of essence, and particularly discloses an amber aroma compound and a preparation method thereof. The chemical name of the compound is 2-ethoxy-2-(1, 2, 3, 4, 5, 5-hexamethylhexyloxy)-[1, 3]-dioxopentane, the compound has amber fragrance and fruity fragrance, and the amber fragrance and the fruity fragrance are integrated on the molecular level; perfume retention test paper data shows that amber aroma and fruit aroma are long in aroma retention time, and the method can be widely applied to the field of daily chemical flavor blending.

Description

Technical Field

[0001] This invention relates to the technical field of fragrances, and specifically discloses an amber fragrance compound and its preparation method. Background Technology

[0002] Amber is recognized as one of the "core structural fragrances" in the perfumery industry. Traditionally, it is described as a warm, rounded, woody-sweet scent with a slight animalic note. It has excellent longevity and fixative properties and is widely used in daily chemical, perfume, and home care products. Its olfactory impression comes from the complex aroma of natural raw materials such as ambergris, vetiver, and patchouli. When heated, genuine amber emits a woody sweetness similar to cypress, but the aroma is lighter and requires high temperatures to release. In modern perfumes, "amber" is mostly an artificially blended fragrance base, such as the classic Ambre 83, which is composed of vanillin, rock rose, patchouli, benzoin, etc., to simulate the warmth of ambergris.

[0003] Currently, most amber-scented raw materials disclosed in literature and patents focus on reproducing the woody-animalistic base of ambergris. For example, patent CN113423700 A discloses an amber-scented fragrance agent, whose disclosed heterocyclic compounds can be used as fragrance ingredients, such as imparting woody and amber-type aroma notes. However, the olfactory performance of such compounds is singular, the fragrance profile is monotonous, and they can only provide a linear amber base, lacking the fruity-sweet layers common in natural ambergris. In domestic and international fragrance and flavor companies, the "amber base" generally uses pure woody amber components such as ambroxanone and cypress ketone, plus a large amount of strawberry aldehyde, peach aldehyde, or lactone fruit fragrance agents for compounding. No compounds have been reported that simultaneously achieve the synergistic release of amber and fruit fragrance within a single molecular skeleton. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an amber aroma compound and its preparation method.

[0005] In a first aspect, the present invention discloses an amber aroma compound, employing the following technical solution:

[0006] An amber-scented compound, chemically named 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane, has the following structural formula:

[0007]

[0008] Secondly, this invention discloses a method for preparing an amber aroma compound, employing the following technical solution:

[0009] A method for preparing an amber aroma compound includes the following steps:

[0010] (1) Preparation of 3,4,5,6,6-pentamethyl-2-heptanol:

[0011] In a hydrogen atmosphere, 3,4,5,6,6-pentamethyl-3-hepten-2-one was subjected to a hydrogenation reduction reaction in the presence of a solvent and a hydrogenation catalyst. After the reaction was completed, the hydrogenation catalyst was filtered off, and 3,4,5,6,6-pentamethyl-2-heptanol was obtained by vacuum distillation.

[0012] (2) Preparation of ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester:

[0013] 3,4,5,6,6-pentamethyl-2-heptanol was esterified with ethoxyacetyl chloride in the presence of a solvent and an acid-binding agent. After the reaction was completed, the mixture was washed with acid, neutralized with alkali, washed with water and dried to remove water, and then distilled under reduced pressure to obtain ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptanol.

[0014] (3) Preparation of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane:

[0015] Ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester was reacted with ethylene glycol in the presence of a solvent, an acid catalyst, and a dehydrating agent. After the reaction was completed, the mixture was neutralized with alkali, washed with water, dried to remove water, and then distilled under reduced pressure to obtain 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane.

[0016] Preferably, in step (1), 3,4,5,6,6-pentamethyl-2-heptanol is obtained by vacuum distillation at 92-94°C and 0.5 kPa.

[0017] Preferably, in step (2), ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester is obtained by vacuum distillation at 160-165°C and 5 mmHg.

[0018] Preferably, in step (3), 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxopentane is obtained by vacuum distillation at 180-185℃ and 133Pa.

[0019] Preferably, in step (1), a wet Raney Ni catalyst is used as the hydrogenation catalyst and anhydrous ethanol is used as the solvent;

[0020] In step (2), pyridine is used as an acid-binding agent and anhydrous dichloromethane is used as a solvent.

[0021] In step (3), p-toluenesulfonic acid is used as an acid catalyst, toluene is used as a dehydrating agent, and ethylene glycol is used as a solvent.

[0022] Preferably, in step (3), the distillation product obtained by vacuum distillation is further purified by column chromatography to obtain 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane.

[0023] Preferably, the stationary phase for the column chromatography is a 200-300 mesh silica gel column, and the eluent is petroleum ether / ethyl acetate = 3:1.

[0024] Preferably, the method includes the following steps:

[0025] (1) Preparation of 3,4,5,6,6-pentamethyl-2-heptanol:

[0026] 92.5 g of 3,4,5,6,6-pentamethyl-3-hepten-2-one, 250 mL of anhydrous ethanol, and 7.5 g of wet Raney Ni catalyst were added sequentially to a reactor. After replacing the air with nitrogen and hydrogen, the reactor was purged with hydrogen to 2.0 ± 1 MPa and the temperature was slowly increased to 80 ± 5 °C. The reactor was stirred and hydrogen was added intermittently. The reaction time was 8–10 h. After the reaction was completed, the reactor was cooled to room temperature in an ice bath. After depressurization, the catalyst was filtered, and the filtrates were combined and concentrated by rotary evaporation under reduced pressure. Finally, 3,4,5,6,6-pentamethyl-2-heptenol was obtained by vacuum distillation.

[0027] (2) Preparation of ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester:

[0028] Under nitrogen protection, 85.2 g of 3,4,5,6,6-pentamethyl-2-heptanol was dissolved in 300 mL of anhydrous dichloromethane. After cooling to 0–5 °C in an ice bath, a mixture of 67.5 g of ethoxyacetyl chloride and 48 mL of pyridine was slowly added dropwise. After the addition was complete, the ice bath was removed and the mixture was stirred at room temperature for 6–8 h. After the reaction was completed, the mixture was washed successively with dilute hydrochloric acid solution, saturated NaHCO3 solution and water, dried with anhydrous Na2SO4 to remove water, and concentrated by rotary evaporation under reduced pressure. Finally, ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptanol was obtained by vacuum distillation.

[0029] (3) Preparation of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane:

[0030] In a three-necked flask, 128.2 g of ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester, 92.0 g of ethylene glycol, 2.5 g of p-toluenesulfonic acid, and 250 mL of toluene were mixed. A water separator and reflux apparatus were assembled, and the mixture was stirred and refluxed at 110–120 °C for 12–14 h. After the reaction was completed, the mixture was cooled to room temperature, neutralized with saturated NaHCO3 solution, and separated. The organic phase was washed with water, dried over anhydrous MgSO4 to remove water, concentrated by rotary evaporation under reduced pressure, and finally the distillation product was obtained by vacuum distillation. The distillation product was further purified by column chromatography to obtain 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane.

[0031] Thirdly, this invention discloses an amber-based composition, employing the following technical solution:

[0032] An amber-based composition comprising the aforementioned amber aroma compounds.

[0033] As a preferred embodiment, the amber-based composition comprises the following components in parts by weight:

[0034] Ambroxol 50 parts, cedrol 40 parts, patchouli oil 30 parts, coumarin 30 parts, ethyl vanillin 20 parts, methyl cedarwood 30 parts, sandalwood 30 parts, isolonga ketone 20 parts, benzyl acetate 30 parts, strawberry aldehyde 20 parts, peach aldehyde 20 parts, pineapple methyl ester 20 parts, sweet orange oil 30 parts, bergamot oil 20 parts, styrax acetate 10 parts, dipropylene glycol 590 parts, 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexoxy)-[1,3]-dioxolane 10 parts.

[0035] Compared with the prior art, the present invention has at least the following beneficial effects:

[0036] 1. The 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane proposed in this invention integrates the dual fragrances of "amber + fruit" at the molecular level: olfactory evaluation shows that it releases a warm and mellow ambergris base while continuously releasing a sweet fruit fragrance; fragrance test data shows that the amber and fruit fragrances have a long-lasting effect and can be widely used in the field of daily chemical fragrance blending.

[0037] 2. The preparation method of this invention uses 3,4,5,6,6-pentamethyl-3-hepten-2-one as the starting reaction substrate. 3,4,5,6,6-pentamethyl-3-hepten-2-one itself does not have a typical fruity aroma. However, this invention chemically modifies its structure in three steps: hydrogenation, esterification, and ketalization, so that it retains its original woody / amber aroma as the main note while adding a fruity aroma. Moreover, the reaction route has fewer steps and the conversion rate of the reaction product is high. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the reaction formula for step (1) in the preparation method of amber aroma compound of the present invention;

[0039] Figure 2 This is a schematic diagram of the reaction formula in step (2) of the preparation method of amber aroma compound of the present invention;

[0040] Figure 3 This is a schematic diagram of the reaction formula in step (3) of the preparation method of amber aroma compound of the present invention;

[0041] Figure 4 The gas chromatogram of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane. Detailed Implementation

[0042] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] Example 1

[0044] An amber aroma compound, the preparation method of which is as follows:

[0045] (1) Preparation of 3,4,5,6,6-pentamethyl-2-heptanol:

[0046] In a 500 mL high-pressure reactor, 92.5 g of 3,4,5,6,6-pentamethyl-3-hepten-2-one, 250 mL of anhydrous ethanol, and 7.5 g of wet Raney Ni catalyst were added sequentially. After purging the air with nitrogen (3 × 0.5 MPa) and hydrogen (3 × 1.0 MPa), the pressure was increased to 2.0 MPa, and the temperature was slowly raised to 80 °C. The reactor was stirred at 500 rpm with hydrogen added every 2 hours for 8 hours. After the reaction was completed, the temperature was lowered to 20 °C in an ice bath. After depressurization, the catalyst was recovered by filtration (washed with 2 × 25 mL of ethanol). The filtrates were combined and anhydrous ethanol was removed by rotary evaporation under reduced pressure (45 °C / 10 kPa). The reaction product was concentrated, and finally, 3,4,5,6,6-pentamethyl-2-heptenol with a GC content of 94.5% was obtained by vacuum distillation (92–94 °C / 0.5 kPa). The reaction formula is shown below. Figure 1 .

[0047] (2) Preparation of ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester:

[0048] Under nitrogen protection, 85.2 g of 3,4,5,6,6-pentamethyl-2-heptanol was dissolved in 300 mL of anhydrous dichloromethane. After cooling to 0–5 °C in an ice bath, a mixture of 67.5 g of ethoxyacetyl chloride and 48 mL of pyridine was slowly added dropwise (completed within 1 hour, with temperature controlled ≤10 °C). After the addition was complete, the ice bath was removed, and the mixture was stirred at 25–30 °C for 6 hours. After the reaction was completed, the mixture was washed successively with 5% hydrochloric acid solution (2 × 100 mL), saturated NaHCO3 solution (100 mL), and water (100 mL). The product was then dried over anhydrous Na2SO4 to remove water, followed by rotary evaporation under reduced pressure (40 °C / 50 kPa) to remove anhydrous dichloromethane. The reaction product was concentrated, and finally, ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptanol was obtained by reduced pressure distillation (160–165 °C / 5 mmHg), with a GC content of 94.2%. The reaction formula is shown below. Figure 2 .

[0049] (3) Preparation of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane:

[0050] In a 1000 mL three-necked flask, 128.2 g of ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester, 92.0 g of ethylene glycol, 2.5 g of p-toluenesulfonic acid, and 250 mL of toluene were mixed. A water separator and reflux apparatus were assembled, and the mixture was stirred and refluxed at 110–120 °C for 12 h. After the reaction was complete, the mixture was cooled to room temperature, neutralized with 100 mL of saturated NaHCO3 solution, and separated. The organic phase was washed with water (2 × 300 mL), dried over anhydrous MgSO4 to remove water, and then subjected to rotary evaporation under reduced pressure (60 °C / 10 kPa) to remove toluene. The reaction product was concentrated, and the final product was obtained by vacuum distillation (180-185℃ / 133Pa). The GC content of the distillate product, 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane, was 94.0%. The distillate product was further purified by column chromatography (stationary phase: 200-300 mesh silica gel, eluent: petroleum ether / ethyl acetate = 3:1) to obtain 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane with a GC content of 99.0%. The reaction formula is shown below. Figure 3 .

[0051] The 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane prepared by the above method has the following NMR spectral characteristics:

[0052] 1H NMR (400MHz, CD3Cl) δ3.92(t,4H),3.42(q,2H),3.02(m,1H),1.96(m,1H),1.65(m,1H),1. 61(m,1H),1.24(d,3H),1.10(t,3H),1.09(d,3H),1.08(d,3H),1.07(d,3H),1.06(s,9H).

[0053] 13 C NMR (100MHz, CD3Cl) δ131.6,63.8,63.8,58.6,49.2,47.6,40.8,34.2,29.6,27.0,27.0,27.0,19.0,16.2,15.2,12.8,11.8.

[0054] Furthermore, the mass spectrometry analysis data of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane prepared by the above method are as follows:

[0055] MS(ESI, m / z) 325.2(M+Na) + ); The theoretical calculation data for high-resolution electrospray ionization mass spectrometry are [C 17 H 34 NaO4] + (M+Na + The actual measured value was 325.2351, not 325.2355.

[0056] See Figure 4 The gas chromatogram confirmed that the product obtained by the above preparation method is 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane.

[0057] Example 2

[0058] An amber-based composition, comprising, by weight parts, the following components:

[0059] Ambroxol 50 parts, cedrol 40 parts, patchouli oil 30 parts, coumarin 30 parts, ethyl vanillin 20 parts, methyl cedarwood 30 parts, sandalwood 30 parts, isolonga ketone 20 parts, benzyl acetate 30 parts, strawberry aldehyde 20 parts, peach aldehyde 20 parts, pineapple methyl ester 20 parts, sweet orange oil 30 parts, bergamot oil 20 parts, styrax acetate 10 parts, dipropylene glycol 590 parts, 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexoxy)-[1,3]-dioxolane 10 parts.

[0060] Of the above components:

[0061] Pogostemon cablin is a woody-earthy essential oil whose main components are patchouli alcohol, patchouli ketone, and terpenoid compounds.

[0062] Sweet orange oil (Citrus sinensis Oil) is a sweet fruity essential oil whose main component is d-limonene and contains small amounts of aldehydes such as sweet orange aldehyde and decanal.

[0063] Bergamot oil is a citrus-floral-herbal complex essential oil with linalyl acetate as the main component and linalool as the auxiliary component. It contains terpenes such as citral and limonene, as well as furanocoumarins.

[0064] Except for the self-made 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane, the patchouli oil, sweet orange oil, bergamot oil and other components are all commercially available raw materials.

[0065] Performance testing

[0066] I. Aroma Evaluation of Compounds

[0067] Eleven perfumers with more than five years of experience were invited to evaluate the aroma of the 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane compound prepared in Example 1 as follows:

[0068] Eleven perfumers unanimously agreed that the compound, in addition to exhibiting the characteristic aroma of amber, also possesses a sweet and fruity fragrance. This result directly verifies, from an olfactory sensory perspective, the dual aroma contribution of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane in fragrance applications, namely, the dual aroma of "amber + fruit." This not only fills the gap in the current lack of natural fruity accompaniments in amber fragrance raw materials but also provides perfumers with the conditions for creating "one fragrance with multiple aromas." It can significantly reduce the amount of fruity auxiliary materials used in the formulation, reduce the complexity and cost of the formulation, and at the same time enhance the naturalness and synergy of the aroma.

[0069] II. Evaluation of Fragrance Retention

[0070] Take one scent test strip, dip it in 0.1g of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane, place the test strip on a scent rack, and have three perfumers smell it every two hours. When two or more perfumers cannot perceive the scent of the test strip, record the lasting time.

[0071] Fragrance retention tests showed that the amber aroma of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane lasted for 48 hours, while the fruity aroma lasted for 24 hours. The 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane compound prepared in this invention exhibits long-lasting, sustained-release fragrance properties, meaning that it can extend the "olfactory freshness" of the finished product after opening. This is particularly suitable for daily chemical applications requiring a long-lasting fragrance, such as laundry detergents and shower gels, and can reduce the amount of traditional fixatives (such as cyclopentadecanolactone), thus reducing the oiliness and potential skin irritation of the formulation.

[0072] III. Fragrance Base Aroma Test

[0073] Prepare fragrance base A and fragrance base B according to the formula in Table 1. Add 10 parts of the target product of this invention, 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane (i.e., the amber fragrance base obtained in Example 2) to fragrance base A. Fragrance base B is prepared without the addition of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane, as a control group.

[0074] Table 1

[0075]

[0076] Seven perfumers with more than five years of experience were invited to evaluate the above fragrance bases. They used scent test strips to sample fragrance bases A and B, placed the strips on a scent rack, and had three perfumers smell them every two hours. When two or more perfumers could not detect the scent on the scent test strips, the lasting time was recorded.

[0077] The perfumer made the following evaluation after assessing the above fragrance base:

[0078] The seven perfumers unanimously agreed that fragrance base A has a more prominent amber scent and a more elegant fruity note than fragrance base B, resulting in a significant improvement in the quality of the fragrance base. Longevity tests showed that fragrance base A's amber scent lasted for 42 hours, and its fruity note lasted for 22 hours; fragrance base B's amber scent lasted for 24 hours, and its fruity note lasted for 12 hours.

[0079] In the fragrance base comparison experiment, fragrance base A containing 10 parts of the target compound showed a significant improvement in amber intensity and fruity elegance compared to fragrance base B which did not contain the component. The overall lasting time was extended from 24 hours to 42 hours, and the fruity lasting time was extended from 12 hours to 22 hours. This demonstrates the synergistic effect of the target compound in the complex fragrance base: on the one hand, its own low vapor pressure structure locks in the top notes, and on the other hand, it forms intermolecular hydrogen bonds and van der Waals networks with woody amber components such as ambroxanone and cedrol, which inhibits the burst release of highly volatile fruity aromas and makes the aroma profile smoother and longer-lasting.

[0080] The technical solution provided by the present invention has been described in detail above. Specific examples have been used to illustrate the principle and implementation of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation and application scope based on the idea of ​​the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An amber odor compound, characterized by, Its chemical name is: 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane, its structural formula is as follows: 。 2. A method for producing the amber odor compound according to claim 1, characterized by, It comprises the following steps: (1) Preparation of 3,4,5,6,6-pentamethyl-2-heptanol: In a hydrogen atmosphere, 3,4,5,6,6-pentamethyl-3-hepten-2-ketone is subjected to hydrogenation reduction reaction in the presence of a solvent and a hydrogenation catalyst, after the reaction is completed, the hydrogenation catalyst is filtered out, and 3,4,5,6,6-pentamethyl-2-heptanol is obtained by reduced pressure distillation; (2) Preparation of ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester: 3,4,5,6,6-pentamethyl-2-heptanol and ethoxyacetyl chloride are subjected to esterification reaction in the presence of a solvent and an acid binding agent, after the reaction is completed, the product is subjected to acid washing, alkali neutralization, water washing and drying to remove water, and then ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester is obtained by reduced pressure distillation; (3) Preparation of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane: Ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester and ethylene glycol are subjected to ketalization reaction in the presence of a solvent, an acid catalyst and a water carrying agent, after the reaction is completed, the product is subjected to alkali neutralization, water washing and drying to remove water, and then 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane is obtained by reduced pressure distillation.

3. The method for producing an amber odor compound according to claim 2, wherein In the step (1), 3,4,5,6,6-pentamethyl-2-heptanol is obtained by reduced pressure distillation at 92-94°C and 0.5kPa.

4. The method for preparing an amber odor compound according to claim 2, wherein In the step (2), ethoxyacetic acid-3,4,5,6,6-pentamethyl-2-heptyl ester is obtained by reduced pressure distillation at 160-165°C and 5mmHg.

5. The method for preparing an amber odor compound according to claim 2, wherein In the step (3), 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane is obtained by reduced pressure distillation at 180-185°C and 133Pa.

6. The preparation method of the amber aroma compound according to claim 2, wherein in the step (1), a wet Raney Ni catalyst is used as the hydrogenation catalyst, and anhydrous ethanol is used as the solvent; in the step (2), pyridine is used as the acid binding agent, and anhydrous dichloromethane is used as the solvent; in the step (3), p-toluenesulfonic acid is used as the acid catalyst, toluene is used as the water carrying agent, and ethylene glycol is used as the solvent. In the step (3), the distillation product obtained by reduced pressure distillation is further purified by column chromatography to obtain 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane.

7. The method for preparing an amber odor compound according to claim 2, wherein The stationary phase of the column chromatography is a silica gel column with a particle size of 200-300 mesh, and the eluent is petroleum ether / ethyl acetate=3:

1.

8. The method for preparing an amber odor compound according to claim 7, wherein It comprises the following steps:

9. The method for preparing an amber odor compound according to claim 2, wherein (1) Preparation of 3,4,5,6,6-pentamethyl-2-heptanol: ​ In a reaction kettle, 92.5 g of 3,4,5,6,6-pentamethyl-3-heptene-2-ketone, 250 mL of anhydrous ethanol and 7.5 g of wet Raney Ni catalyst were sequentially added, the air was replaced by nitrogen and hydrogen, hydrogen was filled to 2.0 ±1 MPa, and the temperature was slowly increased to 80±5℃ for reaction, keeping stirring and interval hydrogenation, the reaction time was 8~10h, after the reaction was completed, the ice bath was reduced to room temperature, the pressure was released, the catalyst was filtered, the filtrate was concentrated by rotary evaporation under reduced pressure, and finally 3,4,5,6,6-pentamethyl-2-heptanol was obtained by reduced pressure distillation. (2) Preparation of 3,4,5,6,6-pentamethyl-2-heptyl ethoxyacetate: Under nitrogen protection, 85.2 g of 3,4,5,6,6-pentamethyl-2-heptanol was dissolved in 300 mL of anhydrous dichloromethane, cooled to 0~5℃ in an ice bath, and then slowly added with 67.5 g of a mixture of ethoxyacetyl chloride and 48 mL of pyridine. After the addition was completed, the ice bath was removed and the reaction was stirred at room temperature for 6~8h. After the reaction was completed, it was washed with dilute hydrochloric acid solution, saturated NaHCO3 solution and water in sequence, dried with anhydrous Na2SO4 to remove water, concentrated by rotary evaporation under reduced pressure, and finally obtained by reduced pressure distillation. (3) Preparation of 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane: In a three-necked flask, 128.2 g of 3,4,5,6,6-pentamethyl-2-heptyl ethoxyacetate, 92.0 g of ethylene glycol, 2.5 g of p-toluenesulfonic acid and 250 mL of toluene were mixed, equipped with a water separator and a reflux device, and kept stirring at 110~120℃ for 12~14h. After the reaction was completed, it was cooled to room temperature, neutralized with saturated NaHCO3 solution, separated, washed with water, dried with anhydrous MgSO4 to remove water, concentrated by rotary evaporation under reduced pressure, and finally obtained by reduced pressure distillation. The distillation product was further purified by column chromatography to obtain 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane.

10. An ambery composition, characterized in that, The amber aroma compound according to any one of claims 1-9.

11. The amber-based composition according to claim 10, characterized in that, By mass fraction, it comprises the following components: Amberone 50 parts, cedrol 40 parts, patchouli oil 30 parts, coumarin 30 parts, ethyl vanillin 20 parts, methyl cedryl ketone 30 parts, sandalwood 30 parts, isolongifolane 20 parts, benzyl acetate 30 parts, strawberry aldehyde 20 parts, peach aldehyde 20 parts, pineapple methyl ester 20 parts, sweet orange oil 30 parts, bergamot oil 20 parts, styracitol 10 parts, dipropylene glycol 590 parts, 2-ethoxy-2-(1,2,3,4,5,5-hexamethylhexyloxy)-[1,3]-dioxolane 10 parts.

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