Perfumes ketones

Other uses include use as a reaction and extraction solvent in pharmaceutical production as an intermediate for the preparation of catalysts, antioxidants (qv), and perfumes and as a feedstock in the production of methyl isopropenyl ketone, 2,3-butanedione, and methyl ethyl ketone peroxide. Concern has also arisen at the large volume of exported MEK which has been covertly diverted and used to process cocaine in Latin American countries... 

Methyl Isopropyl Ketone. Methyl isopropyl ketone [563-80-4] (3-methyl-2-butanone) is a colorless Hquid with a characteristic odor of lower ketones. It can be produced by hydrating isoprene over an acidic catalyst at 200—300°C (150,151) or by acid-catalyzed condensation of methyl ethyl ketone and formaldehyde to 2-methyl-l-buten-3-one, foUowed by hydrogenation to the product (152). Other patented preparations are known (155,156). Methyl isopropyl ketone is used as an intermediate in the production of pharmaceuticals and fragrances (see Perfumes), and as a solvent (157). It is domestically available from Eastman (Longview, Texas) (47). 

Diketones are intermediates for synthesis of perfumes and natural products, and several preparative methods have been developed (327) in the simplest preparative methods, ketone enolates ate oxidatively dimerized (328) ... 

The ketone, ionone, is one of the most important of all the synthetic perfumes, and one most valued by perfumers as being indispensable for the preparation of violet odours. 

Although the odour of the pseudo-ionone does not appear to render it of great importance for its direct use in perfumery, it is capable of serving as raw material lor the production of perfumes, the pseudo-ionone being converted by the action of dilute acids into an isomeric ketone, which I term lonone, and which has most valuable properties for perfumery purposes. This conversion may be effected, for example, by heating for several hours in an oil-bath 20 parts of pseudo-ionone with 100 parts of water, 2-5 parts of sulphuric acid, and 100 parts of glycerine, to the boiling-point of the mixture. 

There are a number of nitro-compounds known under the name of artificial musk, all of which may conveniently be grouped together here. The natural odorous constituents of musk appear to be, in the main, ketonic compounds free from nitrogen, so that the term artificial musk must be understood to mean artificially prepared bodies, having musklike odours, but not having any direct chemical relationship with natural musk perfume. 

Complexes containing one binap ligand per ruthenium (Fig. 3.5) turned out to be remarkably effective for a wide range of chemical processes of industrial importance. During the 1980s, such complexes were shown to be very effective, not only for the asymmetric hydrogenation of dehydroamino adds [42] - which previously was rhodium s domain - but also of allylic alcohols [77], unsaturated acids [78], cyclic enamides [79], and functionalized ketones [80, 81] - domains where rhodium complexes were not as effective. Table 3.2 (entries 3-5) lists impressive TOF values and excellent ee-values for the products of such reactions. The catalysts were rapidly put to use in industry to prepare, for example, the perfume additive citronellol from geraniol (Table 3.2, entry 5) and alkaloids from cyclic enamides. These developments have been reviewed by Noyori and Takaya [82, 83]. 

Consider a quaternary liquid mixture, neroli oil, geraniol, citronellol and solvent, having different volatilities. Neroli oil represents a top note, citronellol and geraniol are body notes. The solvent is ethanol diluted with water to the required concentration. Let us consider this mixture as a base perfume to which musk ketone (4-tert-butyl-2,6-dimethyl-3,5-dinitroacetophenone) is added as an end note or fixative. 

Essential oils are organic compounds derived from flowers, seeds, leaves, roots, resins, and citrus fruits. The structures of many fragrant compounds have been studied, and processes for making these valuable compounds in a laboratory have been developed. There are now approximately 5000 synthetically produced chemicals that are available to a perfumer. These chemicals include vanillin, rose oxides, and the damascenes, or rose ketones. 

Pd supported overlarge-pore tridimensional acidic zeolites such as HFAU are the more active and selective catalysts for the synthesis of bulkier ketones. Thus, in a 0.2% Pd-HFAU catalyst, yield and selectivity from cyclohexanone of 23 and 75% can be obtained in cyclohexylcyclohexanone synthesis. Furthermore, the S5mthesis of aldehydes can only be made selective by joining the hydrogenating metaUic sites (Pd) to basic sites (instead of acidic sites). Thus, 2-ethylhexanal, which is a component of perfumes and fragrances, can be synthesized with high yield and selectivity (64 and 91%, respectively) on a PdKX zeolite. Much lower yields and selectivities are obtained over nonzeolitic materials, such as Pd/MgO. 

Schiff base org chem RR C=NR" Any of a class of derivatives of the condensation of aldehydes or ketones with primary amines colorless crystals, weakly basic hydrolyzed by water and strong acids to form carbonyl compounds and amines used as chemical intermediates and perfume bases, in dyes and rubber accelerators, and in liquid crystals for electronics, shif, bas ... 

SBA is primarily used as feedstock for methyl ethyl ketone. Other uses include hydraulic fluids, industrial cleaning compounds, paint remover, and an extracting agent for oils, perfumes, and dyes. TBA is used mostly as feedstock to make methyl methacrylate and glycol ethers (by reaction with ethylene or propylene oxides.) TBA is also a coproduct with PO, as covered in Chapter 11. 

Uses Manufacture of flotation agents, esters (perfumes and flavors), dyestuffs, wetting agents ingredient in industrial cleaners and paint removers preparation of methyl ethyl ketone solvent in lacquers in hydraulic brake fluids organic synthesis. 

Uses. Polishes, cleaning materials, paint removers, fruit essences, perfumes, and dyestuffs synthesis of methyl ethyl ketone lacquer solvent... 

In general, esters have sweet odors. For this reason, many are useful in perfumes or as flavorings. The boiling points of esters are similar to those of aldehydes and ketones of compcirable molar masses, which means that the boiling points cire lower than comparable alcohols. 

The classical scent of the sea is afforded by ambergris, which is also the best fixative for perfumes. Once secured from whales, ambergris can now be legally provided by chemical synthesis (Science whaling 2000). Other fixatives are obtained from land animals, such as castoreum, civet, and musk. The first one is a phenolic substance and the latter two macrocyclic ketones that have stimulated the earfy methodologies for the synthesis of macrocyclic conqjoimds... 

Cyclohexadecen-l-one can be added to perfume compositions as a substitute for the natural macrocyclic ketone musks. 

The ketone is used in perfume bases for soaps, eau de cologne, and detergent compositions. 

The indane ketone is a musk fragrance that is stable to light and in soap. It is used in perfumes and cosmetics for its fixative properties as well as its fragrance. FCT 1975 (13) p.693. 

The useful disconnection 6a corresponds to Friedel-Crafts acylation of aromatic rings and is the obvious one on the ketone 6 having the perfume of hawthorn blossom. Reaction2 of ether 7 with MeCOCl and AICI3 gives 6 in 94-96% yield—a good reaction indeed. 

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