Styrallyl alcohol

Scheme 4.51 shows the process known to the bulk chemicals industry as SMPO, the styrene monomer-propylene oxide process. Styrene is used in polymers, and propylene oxide derivatives have a wide variety of uses, including as surfactants and in anti-freeze. For the bulk industry, the process is as follows. Addition of ethylene to benzene gives ethylbenzene, which undergoes air oxidation to give the hydroperoxide. Reaction of this with propylene, in the presence of a suitable catalyst, gives styrallyl alcohol and propylene oxide. Styrallyl alcohol is readily dehydrated to styrene. 

Perfumery interest in this process is four-fold. Firstly, one of the major products, styrene, is a starting material for perfume ingredients, as described above. Secondly, the other major product, propylene oxide, is also a precursor for a number of fragrance materials and for dipropylene glycol, one of the major solvents used in perfumes. Thirdly, the intermediate, styrallyl alcohol, is the starting material for a number of esters used in perfumery, the acetate in particular. Fourthly, but by no means least important, the crude styrallyl alcohol contains a small trace of 2-phenylethanol. Since the SMPO process is run on a scale far beyond that of the perfume industry, what is a small... 

STYRALLYL ALCOHOL or STYRALYL ALCOHOL (98-85-1) Combustible liquid (flash point 200°F/93°C cc). Reacts, possibly violently, with oxidizers, alkaline earth and alkali metals, strong acids, strong caustics, aliphatic amines, isocyanates, acetaldehyde, benzoyl peroxide, chromium trioxide, dialkylzincs, dichlorine oxide, ethylene oxide, hypochlorous acid, isopropyl chlorocarbonate, lithium tetrahydroaluminate, nitrogen dioxide, pentafluoroguanidine, phosphorus pentasulfide, tangerine oil, triethylaluminum, triisobutylaluminum. 

Novel mixtures of optical isomers of natural and kosher styrallyl alcohol (a-phenylethyl alcohol), and their corresponding acetate esters of styrallyl alcohol (a-phenylethyl acetate) were prepared by multiple fermentation processes and an azeotropic esterification reaction. In the first step, natural acetophenone was produced by bioconversion of cinnamic acid by Pseudomonas sp. (P), Comanonas sp, and Arthrobacter sp. 6). In the first microbial oxidation process, the side chain of cinnamic acid was oxidized to the ketone to form acetophenone that was transiently accumulated in the fermentation broth (P). The current commercial fermentation process yielded >5g/L of acetophenone in the fermentation broth following 2 days of incubation using Arthrobacter sp. The resulting acetophenone was recovered and purified from the fermentation broth by solvent extraction followed by fractional distillation. Acetophenone itself can be used in creating flavor formulations and in enhancement of aroma and taste or both. 

Finally, the esterification reaction with styrallyl alcohol and acetic acid was carried out under natural reaction conditions using esterification catalysts such as citric acid or by means of bioprocess reactions using commercial esterforming enzymes (5). The catalytic conversion of styrallyl alcohol to styrallyl acetate did not change the stereoisomer ratio. The resulting stereoisomeric mixture of styrallyl acetate was recovered and purified by solvent extraction followed by fractional distillation. 

Methyl benzyl alcohol. SeeCresyl alcohol o-Methylbenzyl alcohol CAS 98-85-1 EINECS/ELINCS 202-707-1 UN 2937 (DOT) FEMA 2685 Synonyms Benzenemethanol, a-methyl- Ethanol, 1-phenyl- Methyl phenylcarbinol Methylphenylmethanol a-Phenethyl alcohol s-Phenethyl alcohol 1-Phenylethanol a-Phenylethyl alcohol Phenylmethylcarbinol Styrallyl alcohol Styralyl alcohol Empirical CsHioO Formula C6H5CH(CH3)OH Properties Colorless liq. mild floral odor sol. in alcohol, glycerol, min. oil, oxygenated and hydrocarbon soivs. si. sol. in water m.w. 122.17 dens. 1.009-1.014 vapor pressure 0.1 mm (20 C) ... 

Stypoi 40-3221] Stypoi 40-3910] Stypoi 40-3941] Stypoi 40-4033] Stypoi 40 74] Stypoi 40-5708] Stypoi 40-5732] Stypoi 40-8006] Stypoi 40-8042] Stypoi 83-2000. See Polyester resin, thermosetting Styracin. SeeCinnamyl cinnamate Styrallyl acetate. See a-Methylbenzyl acetate Styrallyl alcohol. See a-Methylbenzyl alcohol Styrallyl propionate. Seeq-Methylbenzyl propionate... 

The middle part of the perfume is a bouquet of floral notes reduced to their simplest components. Terpineol for lilac, styrallyl acetate for gardenia, phenylethyl alcohol for rose, hydroxycitronellal (10%) for muguet, and benzyl acetate and amyl cinnamic aldehyde for jasmin. 

In Coriandre (Couturier 1973) the top note is of coriander, ylang, styrallyl acetate, and undecylenic aldehyde, with geranium as part of the rose note. The type of rose base, which probably makes up some 10% of the formula, is a classic combination of phenylethyl alcohol, citronellol, geraniol, geranyl acetate, honey notes such as ethyl phenylacetate and phenylethyl phenylacetate, phenylacetaldehyde, rosatol, camomile, and violet leaf. Apart from hydroxycitronellal, Lyral, and phenylacetaldehyde glyceroacetal add to the muguet character. 

Alcohols like 3-methyl-2-buten-l-ol, citronellol, nerol, hotrienol, linalool and 2-phe-nylethanol impart a fresh floral topnote to the whole mango flavour. Artificial mango flavourings may contain diphenyl oxide or styrallyl acetate. 

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