Cinnamic alcohols

Menthol, linalool, citronellol, geraniol, a-ter-pineol, cinnamic alcohol etc. 

Isobutyl, isoamyl, and cinnamic alcohols, menthol and geraniol gave (-nitrobenzyl phthalates which were oily liquids and could not be ciystallised. 

It is a colourless, thick oil, with an odour recalling that of cinnamic alcohol and hyacinths. It is useful in synthetic perfumery in the preparation of bouquets, and it is extremely useful in odours of the type of hyacinth, narcissus, jonquil, and the like. 

Cinnamic alcohol, C Hj. CH CH. CH OH, or y-phenyl-allyl alcohol, is found in the form of esters, principally of either acetic or cinnamic acid in storax, balsam of Peru, and in hyacinth and other essential oils. 

It may be prepared synthetically by reducing cinnamic aldehyde diacetate, and saponifying the resulting cinnamyl esters. Cinnamic alcohol is a crystalline body, although commercial specimens frequently contain traces of impurities which prevent crystallisation. It has the following characters —... 

Cinnamic alcohol forms a phenyl-urethane, melting at 90° to 91°, and a diphenyl-urethane, melting at 97° to 98°. On oxidation it yields cinnamic acid, melting at 133°, and by more thorough oxidation, benzoic acid, melting at 120°. 

Cinnamic alcohol has an odour, not very powerful, but exceedingly delicate, recalling roses and hyacinths, in which types of perfume it is exceedingly useful. It is fairly soluble in dilute alcohol, and can to some extent be separated from alcohols of the geraniol type by means of 30 per cent, alcohol. 

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 —... 

Zimt, m. cinnamon. — weisser —, canella bark, canella. — chinesischer cassia bark. Zimt-. cinnamic cinnamon. -aldehyd, n. cinnamaldehyde, cinnamic aldehyde, -alko-hol, m. cinnamic alcohol, -blute,/. cinnamon flower, cassia bud. -bliltendl, n. cassia oil. zimtbraun, a. cinnamon-brown. Zimtcarbonsaure, /. carboxycinnamic acid, zimt-farbig, -farben, a. cinnamon-colored. Zimt-kaneel, m. canella bark, canella. -kassia, /. cassia bark, cassia, -kassienbl, n. oil of cassia. 

Fig. 17. Chiral acetonide building blocks 36-39, protected 3rd-generation dendrimer 40 and deprotected 2nd-generation dendrimer 41, derived from enantioselectively dihydroxylated styrenes and cinnamic alcohols [74-76]...

Cinnamic alcohol, aroma chemical derived from toluene, 3 234 Cinnamic aldehyde, aroma chemical derived from toluene, 3 234 Cinnamon, 23 155, 165-166 Cinoxate, cosmetic uv absorber, 7 846t Cinromide, 4 359t... 

Ir-catalyzed allylic substitutions employing allylic alcohols as substrates and diethyl malonate as pronucleophile were first reported by Takeuchi and coworkers [11]. Here, the substitution step was found to be preceded by OH activation via transesterification to a malonic ester derivative. The asymmetric alkylation of cinnamic alcohol was similarly accomplished by Helmchen and colleagues, using a PHOX ligand and the procedure described in Section 9.2.3 [19]. 

Another a, i-unsaturated aldehyde analyzed is cinnamaldehyde. Its liquid-phase hydrogenation has been studied in our research group [20, 51, 94], using Pt, Ni and Cu-based tin-modified hi- and organobimetaUic catalysts (in all cases with Si02 as support). The catalytic results obtained showed that in aU cases there was a marked promoting effect of Sn on the selectivity to cinnamic alcohol (UOL). The specific modification of the monometallic systems due to Sn addition from the application of SOMC/M markedly increases the selectivity to UOL, especially in the case of Ni, where it goes from zero selectivity for the monometallic to 25% for the NiSn catalyst. Pt-based systems modified by Sn yield the best Suol values. 

Phenethyl alcohol is qualitatively and quantitatively one of the most important fragrance substances that belongs to the class of araliphatic alcohols. Its lower homologue (benzyl alcohol) and higher homologue (dihydrocinnamic alcohol) also have characteristic odor properties, but are more frequently used in the form of their esters. Cinnamic alcohol, the most important unsaturated araliphatic alcohol, is valuable for both fragrances and flavors. 

Cinnamic alcohol can be dehydrogenated to give cinnamaldehyde and oxidized to give cinnamic acid. Hydrogenation yields 3-phenylpropanol and/or 3-cyclo-hexylpropanol. Reaction with carboxylic acids or carboxylic acid derivatives results in the formation of cinnamyl esters, some of which are used as fragrance materials. 

Production. Cinnamic alcohol is prepared on an industrial scale by reduction of cinnamaldehyde. Three methods are particularly useful ... 

In the Meerwein-Fonndorf reduction, cinnamaldehyde is reduced to cinnamic alcohol (yield ca. 85%) with isopropyl or benzyl alcohol in the presence of the corresponding aluminum alcoholate. 

A 95% yield of cinnamic alcohol is obtained by selective hydrogenation of the carbonyl group in cinnamaldehyde with, for example, an osmium-carbon catalyst [145]. 

High yields of cinnamic alcohol can be obtained by reduction of cinnamaldehyde with alkali borohydrides. Formation of dihydrocinnamic alcohol is thus avoided [146]. 

Uses. Cinnamic alcohol is valuable in perfumery for its odor and fixative properties. It is a component of many flower compositions (lilac, hyacinth, and lily of the valley) and is a starting material for cinnamyl esters, several of which are valuable fragrance materials. In aromas, the alcohol is used for cinnamon notes and for rounding off fruit aromas. It is used as an intermediate in many syntheses (e.g., for pharmaceuticals such as the antibiotic Chloromycetin). 

Cinnamaldehyde is used in many compositions for creating spicy and oriental notes (e.g., soap perfumes). It is the main component of artificial cinnamon oil. In addition, it is an important intermediate in the synthesis of cinnamic alcohol and dihydrocinnamic alcohol. 

Liquidambar acerifolia Max. L. formosana Hance L. maximowiczii Miq. Fon Xian Chi (Liquid amber) (bark, leaf, root) Balsam (resin), cinnamic alcohol, cinnamic acid, 1-borneol, camphene, dipentane, terpene.60-69 Analogous, externally as antiphlogistic and astringent in skin diseases, antihemorrhagic. 

Synthesis in the presence of undissolved substrates has proven useful also in the lipase-catalyzed syntheses of surfactants such as glucose esterified with fatty acids or esters of glycosides [71], but also in more unusual examples such as ibuprofen resolution [72] and the syntheses of the cinnamic alcohol ester of glucuronic acid... 

Glucuronic acid Glucuronic acid Cinnamic alcohol / tert-Butanol 15-22 23... 

Reduction 156 Diacetyi to acetoin (in beer) cinnamic aldehyde to cinnamic alcohol. 

Coniferol (Coniferyl Alcohol or 4-Oxy-3-methoxy cinnamic Alcohol), HO.CH2CH CH.C6H3(OH)-. O.CH3 mw 180. 20, O 26.64% col prisms, mp 73-74° v sol in eth sol in ale alkalies dife sol in hot w, almost insol in cold w prepn other props are given in Beil (Ref 1). It is supposed that four moles of coniferol condense to form Lignin, a cellulose-like substance Refs l)Beil 6, 1131 [ 1093] 2)Hackhs (1944), 221 3)Clift Fedoroff 4 (1946), 17... 

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