Perfume

By the thirteenth century AD, essential oils were being produced along with medicinal and herbal preparations in pharmacies. Around this time improvements in distillation techniques were made, in particular the development of the alembic apparatus, which would eventually estabUsh the quaUty of such matenals. As a result, many of the essential oils in use today are denved from those produced in the sixteenth and seventeenth centunes in terms of odor character, even though production methods have continued to evolve. The current practice of aroma therapy is an indication of this common root of medicinal and fragrance chemistry. 

Kirk-Othmer Encyclopedia of Chemical Technology (4th Edition) 

Odor perception and description are highly subjective in nature. Nevertheless, there is a generally agreed-upon odor vocabulary that is used to characterize individual ingredients and finished fragrances. Table 1 shows some commonly used odor descriptors grouped into five general classifications. 

ightFlora.lFa.mily. The straight floral family contains a large and popular group of flowery odors, most of them easily recognizable. 

Floral Bouquet Family. In the floral bouquet family, fantasy accords are blended into the floral. They all have distinct notes that distinguish one perfume from another. 

Perfume allergy evaluation may be difficult. A complete perfume compound may consist of from 3 to more than 100 basic components (Fisher 1975 a), which can be classified as (1) natural products from flowers, plants, roots, herbs, woods, and gums (2) animal products and their extracts and (3) the synthetic fragrances. 

Perfume screening trays for patch testing has been developed to increase the sensitivity and specificity of perf ume allergy detection (Larsen 1977). In 20 perfume-sensitive patients examined with a screening tray of 15 fragrances, jasmin synthetic, cinnamic alcohol, and hydroxycitronellal were the three most common allergens. Rudzki and Grywa (1977 a) tested 35 essential oils and 4 balsams on 

450 patients. They found a poor correlation between positive reactions to essential oils and to balsam of Peru. When all four balsams (colophony, turpentine, wood tar, and balsam of Peru) were tested they revealed essential oil sensitivity in most of the sensitive patients (72 of 106). 

Odors can affect human psyche. A wonderful aroma from freshly brewed coffee will make us feel awakened and alive. A smell of a well-prepared dish waters our mouth. A perfume worn by a woman can even ehcit sexual desire. On the other hand, putrid vegetables and meat make us sick. 

Odors are brought about by chemicals. A chemical wiU waft through air and arrive at a receptor in our nose, and starts the sensation of smeU. This suggests that odor-causing chemicals must be fairly volatile. That is, they have to have significant vapor pressures (or a significant number of molecules in the air). Therefore, the chemicals that cause this sensation are relatively small molecules. 

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Its chief importance is as a source of cinnamic acid by condensation with sodium ethan-oate and ethanoic anhydride and as a source of triphenylmethane dyestuffs by condensation with pyrogallol, dimethylaniline, etc. It is also used in the manufacture of perfumes. 

CH3 CH0H CH20H, a colourless, almost odourless liquid. It has a sweet taste, but is more acrid than ethylene glycol b.p. 187. Manufactured by heating propylene chlorohydrin with a solution of NaHCO under pressure. It closely resembles dihydroxyethane in its properties, but is less toxic. Forms mono-and di-esters and ethers. Used as an anti-freeze and in the preparation of perfumes and flavouring extracts, as a solvent and in... 

CifiHjoO. A yellow liquid b.p. 330°C. The perfume base obtained from the scent glands of the Tibetan musk deer also available by synthesis. 

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. 

SNG Substitute natural gas. soaps Sodium and potassium salts of fatty acids, particularly stearic, palmitic and oleic acids. Animal and vegetable oils and fats, from which soaps are prepared, consist essentially of the glyceryl esters of these acids. In soap manufacture the oil or fat is heated with dilute NaOH (less frequently KOH) solution in large vats. When hydrolysis is complete the soap is salted out , or precipitated from solution by addition of NaCl. The soap is then treated, as required, with perfumes, etc. and made into tablets. 

CaH803. Fine white needles, m.p. 82°C, b.p. 285°C, strong vanilla odour, characteristic taste. It occurs extensively in nature, and is the odoriferous principle of the vanilla pod it can be obtained from the glucoside coniferin. Vanillin is made commercially from the ligno-sulphonic acid obtained as a by-product in the manufacture of wood pulp. It is one of the most important flavouring and perfuming... 

Spirit G (petroleum ether) 0.645 30-75 (approx.) Petroleum gas equipment, perfume extraction... 

We made this important intermediate (A) in a slightly different way (frame 318), but this is how it s made industrially for use in perfumes and flavours (Pure. Annl. Chem.. 1975, 43, 527). How would you extend this synthesis to make TM 324 ... 

Revision Problem 4 Musks are compounds which have some pleasant smell themselves, but function chiefly by retaining and enhancing the perfume of other compounds. How might celestoHde , a modem musk, (TM 398) be made ... 

Cis-Jasmone (TM 422) is an important ingredient inmany perfumes. There are several obvious disconnections and it may help you to know that cychsation of the diketone 422A does indeed selectively give cis-jasmone. 

The lonones are fragrant substances present in the scent of ms and are used in perfume A mixture of a and 3 lonone can be prepared by treatment of pseudoionone with sulfuric acid... 

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