Perfume constituents

Selective hydroformylation of DCPD has afforded monoformyl derivatives (13), useful as perfume constituents and synthetic mbber intermediates (69) and dimethanohc derivatives useful for the manufacture of polycarbonates and polyesters (70). 

This approach constitutes a simple alternative to high dilution techniques for intramolecular esterification. The pentadecanolide is a perfume constituent from angelica root oil. 

It is reported that the two-phase carbonylation methodology has been used on a pilot plant scale by Montedison [31 ] for the conversion of benzyl chloride to phenylacetic acid for use in perfume constituents and pesticides (eq. (8)). The carbonylation is run in a biphasic medium employing diphenyl ether and aqueous 40 % sodium hydroxide as solvents. The catalyst system consists of a cobalt carbonyl complex and a benzyltrialkylammonium surfactant. The reaction takes place at low temperature and CO pressure, while benzyl chloride is added continuously to the reaction mixture. 

The perfume constituent 5-nonene-2-one (5) was obtained in 61 % yield via cross-metathesis of silylated allyl acetone with two equivalents of 4-octene (using Re207/Mo03/Al203/Me4Sn as catalyst) and elimination of the protecting group (Eq. 16) [40]. 

The perfume constituent non-5-ene-2-one is obtained in 61% yield via crossmetathesis of silylated allyl acetone with 2 equiv of oct-4-ene, reaction (18), using Re207/Mo03/Al203/Me4Sn as catalyst (Warwel 1989c). 

GPRI 7597 perfume constituent Irons- 1,2-DlchloroeUiylene permeability inhibitor, industrial coatings Suzorite 60-HK Suzorite 80-SF Suzorite 200-HK Suzorite 325-HK PET modifier... 

Shown below is the final step in a synthesis of an important perfume constituent, m-jasmone. Which reagents would you choose to carry out this last step ... 

To overcome possible false positives (mainly due to co-elutions of perfume constituents exhibiting isobaric ions in common with PASs) and false negatives (due to the shift that a large non-related eluting peak in front of the SIM window can promote on the PAS retention time), a recent paper proposed successively injecting the sample into two columns... 

When there is no concern about the matrix (fragrance concentrates and extracts, alcoholic perfumery) the complexity lies in the huge number of perfume constituents, which may interfere with PASs. GC with MS detection in SIM mode gives the most satisfactory results for routine determination. Among more sophisticated multidimensional approaches, GC-MS/MS lowers possible false positives and negatives, whereas... 

C10H13O. B.p. 225-226"C. A terpenic alcohol and a constituent of neroli, petit-grain and bergamot, and of many other essential oils. Nerol has a blander smell than its isomer, geraniol, and is more valuable as a constituent of perfumes. 

Bl cetyl. Biacetyl [431-03-8] (2,3-butanedione) is a greenish yeUow liquid with a quinone odor. Biacetyl occurs naturally in bay oil and is readily soluble in organic solvents. It is a constituent of many food aromas, eg, butter, and is commonly used to flavor margarine. Flavor-grade biacetyl was available at 20.40/kg in July 1993, and is used as an odorant for coffee, vinegar, tobacco, and in perfumes. 

Bergamot. Bergamot oil is produced by cold expression from peels of fmits from the small citms tree. Citrus bergamia. The fmits are inedible and of httle value. Bergamot is grown mainly in southern Italy and northern and western Africa. The oil is used to impart a sweet freshness to perfumes. Its largest chemical constituent, to the extent of 35—40%, is linalyl acetate [115-95-7] (1), with a much smaller amount of citral [5392-40-5] (2) as an important odor contributor. 

Ced rwood. Many varieties of cedarwood oil are obtained from different parts of the world. They are produced mainly by steam distillation of chipped heartwood, but some are also produced by solvent extraction. The oils, which vary significantly ia chemical composition, are used ia perfumes as such, but the main uses are as distillation fractions and chemical derivatives. For the latter purposes the most used oils, which are similar ia composition, are from Texas ia the United States (Juniperus mexicand) and from China Cupressusfunebris). The principal constituents of these oils are cedrene [11028-42-5] (4), thujopsene [470-40-6] (5), and cedrol [77-53-2] (6). The first two of these are obtained together by distillation and used mostiy ia the form of acetylated derivatives. Cedrol is used as such and, to a greater extent, as its acetate ester. 

Rose. Rose is one of the most important florals ia perfumery, the most valuable derivatives of which are produced from Rosa damascena, which is grown principally ia Bulgaria, but also ia Russia, Turkey, Syria, India, and Morocco. The concrete, absolute, and steam-distilled essential oil (rose otto) are particularly valuable perfume iagredients. Careful handling and processiag of freshly picked flowers are required to produce these materials of warm, deeply floral, and rich odor quaUty. They are complex mixtures of which citroneUol (9), geraniol (8), phenethyl alcohol [60-12-8] (21), and P-damascenone [23726-93 ] (22) (trace component) are important odor constituents. 

Perfumes and Cosmetics. Vanillin, a crystal, is the main constituent of the vanilla bean. Its importance can be illustrated by the fact that human preferences in fragrances and in flavors, as determined by various studies, comprise three main smells or tastes rose, vanilla, and strawberry. 

Flavor-Masking Deodorant. In addition to its use as a constituent of perfume compositions, vanillin is also useful as a deodorant to mask the unpleasant odor of many manufactured goods. As a masking agent for numerous types of ill-smelling mass-produced industrial products, particularly those of synthetic mbber, plastics, fiber glass, inks, etc, vanillin finds extensive use. It is often the most inexpensive material for the amount of masking effect it provides. Only traces are required for this purpose as the odor of vanillin is perceptible in dilutions of 2 x 10 mg/m of air. Cmde vanillin is acceptable for such purposes. 

Essential oils are obtained from fmits and flowers (61,62). Volatile esters of short- and medium-chain carboxyHc acids or aromatic carboxyHc acids with short- and medium-chain alcohols are primary constituents of essential oils, eg, ethyl acetate in wines, brandy, and in fmits such as pineapple ben2yl acetate in jasmine and gardenia methyl saHcylate in oils of wintergreen and sweet birch. Most of these naturally occurring esters in essential oils have pleasant odors, and either they or their synthetic counterparts are used in the confectionery, beverage, perfume, cosmetic, and soap industries (see Oils, essential). 

Bodies of an alcholic nature play a very important part in both natural and synthetic perfumery. They are found to a very large extent in essential oils, both in the free state and also in the form of esters. Some that have not so far been recognised as constituents of essential oils, have been found to be so highly odorous, and so useful as perfume materials, that they are prepared artificially, and enter largely into the composition of the synthetic perfumes which to-day are indispensable to the manufacturer of perfumes. It is obvious that those alcohols which are soluble in water, such as methyl and ethyl alcohols, although they may be original constituents of some essential oils, are removed by the ordinary distillation processes, so that they do not, in fact, appear in the essential oil as found in commerce. 

The higher aliphatic alcohols, from octyl alcohol upwards, have-recently been introduced as perfume materials with considerable success. Only one or two of them, such as nonyl and undeeylenic alcohols, have so far been detected as natural constituents of essential oils, but other members of the series are prepared artificially, and are employed in minute quantities in the preparation of perfumes with characteristic, fruity bouquets. These alcohols are greatly diminished in perfume value by traces of impurities. According to H. J. Prins, the first interesting member of the series is octyl alcohol it has a very sweet, rose-like odour, and is especially suitable for giving a rose perfume that pecnliar sweet smell which distinguishes a rose from a rose perfume. This feature of the aliphatic alcohols diminishes in the series from Cg to Cjg. 

It is fairly soluble in dilute alcohol, and in about 35 parts of water. It can therefore be fairly easily separated from less soluble constituents by shaking with 5 or 10 per cent, alcohol. Apart from its actual perfume value, benzyl alcohol is of considerable value to the perfumer, since it acts as a very valuable fixative, and is, moreover, one of the best-known solvents for artificial musk. 

The esters play a most important part in the economy of plant life, and are highly important constituents of numerous essential oils. Indeed, in many cases they are the dominating constituent, and the oil may be said to owe its perfume value largely, or in some cases almost entirely, to the esters it contains. 

Ethyl Cinnamate.—The cinnamic ester of ethyl alcohol is a natural constituent of a few essential oils, including camphor oil and storax. It is formed synthetically by condensing cinnamic acid and ethyl alcohol by dry hydrochloric acid gas. It has a soft and sweet odour, and is particularly suitable for blending in soap perfumes. It is an oil at ordinary temperatures, melting at 12°, and boiling at 271°. Its specific gravity is 1 0546, and its refractive index 1 5590. 

Benzyl Acetate.—This ester is a constituent of the oils of jasmin, ylang-ylang, and similar flower oils. It has not a very intense odour, but is essential to the successful production of such perfumes as artificial jasmin. It has the formula CgHg, CH2. O. OCCH3. It is a colourless oU, boiling at 206° at ordinary pressure, and has a specific gravity 1-0570 at 16° and a refractive index 1-5034 . The propionic ester has the formula C0H5CH2OOCCH2CH3, and closely resembles the acetate in odour. 

Benzyl Ginnamate.—The cinnamic acid ester of benzyl alcohol is a natural constituent of storax, tolu, and Peru balsams. It is a crystalline Bubstance with a characteristic sweet balsamic odour. It may be prepared by heating sodium cinnamate, alcohol, and benzyl chloride together under a reflux condenser. It is a useful ester where a sweet balsamic odour is required to be introduced into a perfume, especially cf the heavy type. It forms white, glistening prisms, which melt at 39°, and.decompose when heated to 350°. The best commercial specimens have the following characters —... 

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