Rose odour

CMe2=CH. CH2. CH . CHMe. CH. CHMeOH, has the same odour but more pronounced, and suggestive of tea roses. 2 Di-methyl-critronellol, CMe2=CH. CH. CH. CHMe. CHaCMe OH, has the rose odour but is also slightly camphoracious (as is to be expected with a tertiary alcohol) 1 ethyl citronellol has a very fine odour of roses and 2 di-ethyl-citronellol is like the di-methyl compound but the rose odour is more pronounced 1 phenyl citronellol is very strong. 

By heating geranyl chloride with sodium alcoholate geranyl ethyl ethOr was obtained. This body, 10 17 - - CI2H5, is an oil with a faint rose odour, having the following characters —... 

Citronellol and rhodinol have faint but sweet rose odours. 

Mentho-citronellol or menthonyl alcohol, CjjHjoO, is an alcohol of delicate rose odour, and is synthetically prepared as follows —... 

Methyl-heptenol is an alcohol with a delicate rose odour, of the formula CgHjgO. It occurs in Mexican and Cayeme linaloe oil, and is-prepared by reducing methyl-heptenone, and has the following characters —... 

Phenyl-ethyl alcohol, CgH. CHj. CHjOH, is the next highest homologue of the benzyl alcohol series. It is found naturally in rose -and neroli oils but as it is very soluble in water, it practically disappears from the distilled otto of rose and is dissolved in the rose water. Hence otto of rose with its beautiful perfume does not truly represent the odour of the rose. By the use of various isolated and synthetic bodies an artificial otto can be prepared which more closely resembles the rose odour than does the natural otto itself. But it is doubtful whether any really good artificial otto of rose can be prepared without some natural otto as its basis. 

Phenyl-ethyl alcohol, or benzyl carbinol, has been known for many years, but its powerful rose odour has been entirely overlooked, its discovery having been made by an ordinary research chemist and not a perfumery expert. Its preparation was described in the Berichte (9, 373) in 1876, but the product there noted was evidently impure, as its boiling-point is recorded as 212°. Commercial specimens vary greatly in both their odour and their keeping properties, some samples deteriorating in odour very rapidly. It is, therefore, very important to -obtain it in a state of the highest purity. It has the following characters —... 

It is suitable, not only for rose odours, but also for blending with almost any flower oil. Phenyl-ethyl alcohol forms a solid compound with chloride of calcium, which is very useful for its purification. On oxidation it is converted into a mixture of phenyl-acetaldehyde and phenyl-acetic acid. The last-named body forms an ethyl ester melting at 28°, which serves for its identification. 

The rose odour is still further modified by the presence of the five carbon acid radicle, and judicious blending of the various geranyl esters is capable of giving numerous characteristic bouquets to the various rose odours. This ester boils at 135° to 138° at 10 mm. pressure. 

The odour of the ester varies slightly, according as it is made from the dextro-rotatory or the laevo-rotatory variety of the alcohol. That of the former is rather fuller and deeper in its rose odour than that of the latter. Both esters blend excellently with the corresponding citronellols, and are very useful in preparing synthetic otto of rose. 

When perillic acid is dissolved in five times its weight of amyl alcohol and is reduced by sodium at the boiling temperature, dihydro-perillic acid, CjoH Oj, is obtained. This acid melts at 107° to 109° C. By the reduction of its methyl ester by means of sodium, dihydroperillic alcohol is fornned, which is a liquid with a rose odour and having the following characters —... 

This acid, CgH. CH. CH COOH, has a sweet and powerful odour, and can be used to advantage in many rose odours. It is recommended especially for perfuming powders and sachets. It is a crystalline compound, melting at 47° and boiling at 280°. It can be obtained by the reduction of cinnamic acid by means of sodium. 

The phenyl acetic acid esters are highly valuable intermediates for a lot of applications. Among them, they are applied for the synthesis of fragrances e.g. ethyl ester (honey odour), isobutyl ester (sweet roses odour). The present industrial process for phenyl acetic esters starts from benzylchloride and uses the reactions with KCN to form benzylcyanide 7 (Eq. 15.2.4) and followed by hydrolytic cleavage. 

Phenylethanol is one of the most widely used fragrance chemicals, with worldwide production in excess of 7,000 tons per annum. 2-Phenylethanol is often used in high quantities as fragrance with sweet and rose odour. It is particularly well suited as a fragrance for the production of soap because of its stability towards alkalines. 

Purify geraniol by fractional distillation. It has a sweet rose odour when pure, and the UV has... 

Alcohols in peas are mostly formed from enzymatic oxidation of lipids. Physical damage, storage and processing of seeds could lead to the formation of alcohols (Eriksson, 1967 de Lumen et al., 1978 Oomah Liang, 2007). Volatile alcoholic compounds have distinct characteristics and they could therefore affect the taste and flavour of peas. For example, 1-propanol has an alcoholic odour and a fruity flavour 2-methyl-l-propanol has a wine odour, 3-methyl-l-butanol has a fruity, banana, sweet odour with a bittersweet taste 1-hexanol has an herbaceous, mild, sweet, green fruity odour and an aromatic flavour 1-heptanol has an aromatic and fatty odour and a spicy taste, whereas 1-octanol has a fresh, orange-rose odour and an oily, sweet taste (Burdock, 2002). 

Oil with rose odour. B.p. 134r-5°/10 mm. Polymerizes on standing. 

The principal constituent of the oil is guaiac alcohol, or guaiol. This oil, which has what is generally termed a tea-rose odour, is occasionally used as an adulterant for otto of rose. 

Bose and diphenyl ether Similar odour Fine rose odour Bose... 

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