Uses of Ambergris
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Background and overview
Ambroxan
ether is also known as bicyclic dihydrogacaine ether, 1,1,6,10-tetramethyl-5,6-cycloethoxy decalin, Amberoxan, Ambropur, Ambroxide. Natural ambergris is a high-grade spice, it comes from the gray soft stones in the stomach of sperm whales, and the amount is very small. Ambergris is a artificially synthesized spice with ambergris fragrance, which is used as a substitute for natural ambergris. Colorless to white crystals. The relative molecular mass is 236.34. The melting point is 75～76℃. The boiling point is 120°C (0.133×103Pa). The flash point is 161°C. Specific optical rotation -29° (c=1, toluene).
Ambergris Use
Ambergris "Ambergris effect" can greatly improve the diffusion effect of the essence. It is used in the essence of high-end perfumes and cosmetics. It is non-irritating to the human body. It is suitable for the fragrance of skin, hair and fabrics, such as soap and talcum powder. , Creams and shampoos and other fragrances and fixes fragrance. The application of ambergris fragrant raw materials in cigarettes. Laibaitang substances are the key aroma components of oriental tobacco. Ambergris is one of the most prominent flavors and makes an important contribution to the smoke of mixed cigarettes. Ambroxol is widely used in flue-cured tobacco and perfume industries. Ambroxol is used as a flavoring additive in the cigarette industry It harmonizes with the characteristic aroma of tobacco, and can mask the odor. Even if it is used in a small amount, it can also improve the flavor quality of tobacco. It is especially suitable for blended cigarettes to add flavor and enhance the oriental The flavor of type tobacco.
In foreign countries, sclareolide, norambrial glycol and ambroxol are loaded in a solvent and sprayed on cut tobacco in an applied amount of 5,000 to 3,000 to improve the flavor of cigarettes. Due to its small molecular weight, strong volatility, and low threshold.
Ambroxol is prepared into carbonate (Carbonate-I, Chart2) latent aroma substance, which has a large molecular weight and is not easy to volatile. During the smoking process of cigarettes, the aroma precursor, norambasol carbonate is decomposed at high temperature and cyclized at the same time to produce the aroma components of norambasol. Cigarette smoke has obvious woody and amber aromas. Hunan China Tobacco Industry Co., Ltd. prepares the oxalate (Oxalate-II, Chart2) latent aroma material form of ammbroxol, and then adds it to the tobacco by adding surface aroma, flavoring or flake flavoring. During the smoking and burning process of the cigarette, the aroma-causing substance of ambre is released uniformly, so that the cigarette has a more obvious ambergris aroma.
Manufacturing method
Method 1: Use sclareol as a raw material for two-step oxidation, namely alkaline oxidation and weak acid oxidation. The oxidant can be potassium permanganate, ozone or sodium (or potassium) dichromate in sulfuric acid solution, and then the oxidation It is saponified, dehydrated, and lactonized to obtain the ambergrolactone. Then the lactone is reduced to the ambroxol with lithium aluminum hydride in ether (or borane in tetrahydrofuran). Using D-camphor-β-sulfonic acid as the cyclizing agent, decyclizing the diol, and then dehydrating under the action of aluminum trioxide, the ambroxan ether can be prepared. In addition to obtaining the ambroxan ether by this method, the isomer of the ambroxan ether, the bicyclic homofarnesol, that is, Labaidan-6-en-12-ol (colorless crystals, melting point) can also be obtained. 20℃, there is also ambergris scent).
Method 2: Synthetic route using diol 2 as an intermediate Starting from (-)-sclareol 3 derived from sclareol extract, the first artificial synthesis of ambergris ether, with a total yield of 52%. Sclareol 3 is oxidized with chromium trioxide and degraded to lactone 4. Lactone 4 is reduced by lithium tetrahydroaluminum to obtain diol 2; diol compound 2 is activated by p-toluenesulfonyl chloride and then carried out under the action of alkali sodium hydride Intramolecular cyclization yields anambergris 1. The disadvantage of this route is that it needs to use chromium trioxide as an oxidant, which will generate a large amount of polluted chromium-containing wastewater. At the same time, it needs to use more dangerous lithium aluminum hydride and sodium hydride, as shown in the
The possibility of synthesizing the ambroxan ether by stereoselective cyclization with nerolidol 5 as the raw material. Starting from nerolidol 5, (E, E)-homoaclic acid 8 and another isomer are obtained through bromination, nitrification and hydrolysis, with a ratio of 8:2. Acid 8 is purified by column chromatography through the formation of ethyl esters. The ester of 8 is hydrolyzed under alkaline conditions to obtain an acid with a purity of 98%. Acid 8 is in dichloromethane, boron trifluoride ether is used as Lewis acid, and reacted at -20°C for 60 minutes to obtain cyclized product 4 with a yield of 38%. Then, the compound 4 is reduced with lithium aluminum tetrahydrogen to obtain diol 2. The diol 2 uses pyridine as a solvent and is heated in the presence of p-toluenesulfonic acid as a catalyst to obtain (±) ambergris ether 1 by cyclization. The rate is 75%:
Method 3: Synthetic route without intermediate diol 2 Starting from dihydro β-ionone 35, 4-(2,2,6-trimethyl-1-cyclohexene)-2-methylbutanal 47 is obtained by Darzens reaction, and then 48 is obtained by reaction with malonic acid , And then after several steps of reaction to get ambre-1. The product obtained here is a racemic product, and its aroma quality is slightly different from (-)-Ambroxan
