Patchouli odorants

C15H24O, Mr 220.36, a colorless liquid, 0.997-1.005, npj1 1.498-1.503, with a dry woody, earthy-camphoraceous patchouli odor. Major use is in perfume oils for soaps and fabric detergents. 

The Prins reaction with formaldehyde, acetic acid, acetic anhydride, and camphene gives the useful alcohol, 8-acetoxymethyl camphene, which has a patchouli-like odor (83). Oxidation of the alcohol to the corresponding aldehyde also gives a useful iatermediate compound, which is used to synthesize the sandalwood compound dihydo- P-santalol. 

Patchouli alcohol. Patchouli oil comes from Pogostemonpatchouli and the main constituent is patchouli alcohol [5986-55-0] (105) or patchoulol. Another component of the essential oil is norpatchoulenol (106), a norsesquiterpene derivative as a minor (3—5%) constituent, important ia determining the overall odor of the essential oil (197). The price of patchouli oil ia 1995 was 20.90/kg from Indonesia (69). Alarge proportion of the oil (40—60%) is comprised of sesquiterpene hydrocarbons that do not have much odor value. World production of the oil was at about 750 t ia 1984. It is valuable ia perfumery bases because of its characteristic woody, herbaceous odor (198). 

Patchouli oil is produced by steam distillation of the dried leaves of Pogostemon cablin (Blanco) Benth. (Lamiaceae). It is a reddish-brown to greenish-brown, more or less viscous liquid with a characteristic, slightly camphoraceous, woody balsamic odor. 

The presence of certain metals such as iron, particularly in the presence of water, can act as a catalyst for many types of chemical reaction including oxidation, and iron can itself form highly colored reddish-brown complexes with many materials. A common test for the presence of iron in essential oils such as patchouli, where it can occur as a result of the distillation process being carried out in nonstainless steel equipment, is to mix the oil with benzyl salicylate. If iron is present, a reddish color develops after a few moments. Fortunately iron can quite easily be removed by treatment with citric, tartaric, or oxalic acids, with which it forms stable sequestered complexes. Compounds that show this type of discoloration can sometimes be recovered in this way if not too old, whereas products containing water (which may be the source of the iron contamination), such as alcoholic lotions, will usually show too much odor deterioration, by the time the discoloration has developed, to make recovery possible. 

In the 1800s shawls imported from India were often packed with patchouli leaves to ward off insects, thus permeating the clothing with the distinctive odor. 

Essential oils or volatile oils are useful for their fixative properties as well as their odor. Among the fixative essential oils are clary, sage, ventiver. Patchouli orris, and sandalwood, etc. Usually, they have low boiling points not more than 285-290°C. 

Figure 4.33 Some odorous sesquiterpenes from vetiver and patchouli...

The odor and flavor of Chocarom Pyrazine is reminiscent of the warmth of cocoa and hazelnut. It is slightly musky animalic, with patchouli and vetiver tones and a mentholic note. The odor character is displayed graphically in Figure 2. 

Patchouli olL Reddish-brown to brown, viscous oil with a typical woody, camphor-like earthy, balsamy sweet odor. 

Composition Main component and responsible for the woody odor is (-)-patchouli alcohol (ca. 40-50%) C15H26O, Mr 222.37, colorless crystals with... 

S)-(+)-Carvone produces the typical odor and taste of caraway, whereas its (R)-(-)-enantiomer in the oil of spearmint from Mentha spicata (Labiatae), in contrast, smells like peppermint (p. 18). (-)-Patehoulol (also referred to as patehoulialeohol p. 40) smells intensely woody and earthy with a touch of camphor, similar to the natural oil of Patchouli used in perfumery, while the weak odor of the synthetically produced (+)-enantiomer is quite untypical. 

Vetiver and patchouli are two oils of great importance in perfumery (Williams, 1996, 2004). Both contain complex mixtures of sesquiterpenoids, mostly with complex polycyclic structures (Sell, 2003). The major components of vetiver oil are a-vetivone (136), b-vetivone (137), and khusi-mol (119), but the most important components as far as odor is concerned are minor constituents such as khusimone (151), zizanal (152), and methyl zizanoate (153). Nootkatone (154) is an isomer of a-vetivone and is an important odor component of grapefruit. Patchouli alcohol (145) is the... 

Patchoulol is the major active ingredient and the most odor-intensive component of patchouli oil, the volatile oil of Pogostemon cablin, one of the most important raw materials of perfumery,... 

As to influences of the familiarity of or experience with fragrances, Kawano (2001) reported that the odors of lemon, lavender, patchouli, marjoram, rosemary, and sandalwood increased a activity over occipital electrode sites in subjects to whom these fragrances were well known. On the... 

The hydroformylation of allyl ethers with cumenyl, isobornyl, 2-methyl-2-pentanol, and terpinyl groups was patented by IFF (Table 6.4) [186]. In all cases, the linear and branched aldehydes were formed. After distillation, the odors of the linear compounds were evaluated. The isobornyl-derived aldehyde was reduced to give a corresponding hydroxy butylether with a typical patchouli aroma. 

Patchouli Patchouli oil is produced by steam distillation of the dry leaves of Pogoste-mon cablin, a shrub-like plant that originated in the Philippines and Indonesia. Most production is done in Indonesia. Patchouli oil has a wonderfully rich odor profile which is described as warm, sweet, herbaceous, spicy, woody, and balsamic. It is relatively inexpensive for a namral product and is usually available in abundance. For these reasons, patchouli oil is very widely used in many kinds of perfumes. Its main odor-donating constituents are polycyclic alcohols. The best known of these, patchouli alcohol [5986-55-0] (23), is present in the oil to the extent of about 30%. However, it is believed that... 

As a consequence of their higher molecular weight, sesquiterpenoids are less volatile than their monoterpenoid counterparts. This means that a smaller percentage find use in perfumery. However, some of those that do have an odor, have low thresholds and/or high intensities. They often have fixative properties and are generally used as base notes, in particular as woody notes, in perfumes. The use of sesquiterpenoids in perfumery was reviewed by McAndrew (322). Three of the most important sesquiterpenoid-rich oils are sandalwood, patchouli, and vetiver. 

Patchouli oil is distilled from the fermented leaves of Pogostemon cablin. Its main constituent is patchouli alcohol [5986-55-0] (257), also known as patchoulol. However, this and the other major components have relatively little odor and the characteristic scent arises from some of the minor compounds present. Vetiver oil is distilled from the roots of the tropical grass Vetivera zizanoides. It contains a very large number of sesquiterpenoids, a-vetivone (258), (3-vetivone (259), and khusimol (260) accounting for 35% but, as with patchouli, it is a number of minor components that are responsible for its valuable odor. Details of patchouli and vetiver chemistry can be found in Chapter 7 of the book by Sell (323). 

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