Benzyl alcohol, purification

It is important to note that the one-step conversion of 27 to 28 (Scheme 4) not only facilitates purification, but also allows differentiation of the two carbonyl groups. After hydrogenolysis of the iV-benzyl group (see 28—>29), solvolysis of the -lactone-ring in 29 with benzyl alcohol and a catalytic amount of acetic acid at 70 °C provides a 3 1 equilibrium mixture of acyclic ester 30 and starting lactone 29. Compound 30 can be obtained in pure form simply by washing the solid mixture with isopropanol the material in the filtrate can be resubjected to the solvolysis reaction. 

Biegert T, U Altenschmidt, C Eckerskorn, G Euchs (1995) Purification and properties of benzyl alcohol dehydrogenase from a denitrifying Thauera sp. Arch Microbiol 163 418-423. 

As part of the same study, the capacity of this novel resin to act as an allyl cation scavenger was demonstrated in a palladium-catalyzed O-alloc deprotection of O-alloc benzyl alcohol (Scheme 7.107) [125], Benzyl alcohol was obtained in high yield with only trace amounts of by-product, thereby eliminating the need for further purification. The resulting C-allylation of the resin was evident from the presence of C-allyl signals in the relevant MAS-probe 1H NMR spectrum. 

Benzyl alcohol, 23, 14 BeNZYLAMINE, a-METHYL-, 23, 68 Benzyl carbamate, 23, 14 Benzyl chloride, 21, 99 Benzyl chloroeormate, 23, 13 Benzyl cyanide, 23, 71 Bisulfite compound, use for purification of an aldehyde, 23, 78 use for purification of a ketone, 23, 79 Blood, defibrinated, 21, 53 Booster pump, use of, for hydrogenation, 23, 69... 

Toluene is, in low conversion, oxidized, with air, in the liquid phase to benzyl hydroperoxide, which yields mainly benzyl alcohol and some benzaldehyde upon hydrolysis, for example, in the presence of a cobalt salt. Benzyl alcohol thus obtained requires a more thorough purification for use in perfumes and flavors. 

Methyl n-amyl carbinol. 247, 254 Methyl n-amyl ketone, 482 Methylaniline (mono), pure, from commercial methylaniline, 562, 570 P-Methylanthraquinone, 728, 740 Methyl benzoate, 780, 781 p-Methyl benzyl alcohol, 811,812 Methyl benzyl ketone, 727, 735 Methyl y-bromocrotonate, 926, 927 2-Methyl-2-butene, 239 Methyl n-butyl carbinol, 247,255 Methyl n-butyl ether, 314 Methyl n-butyl ketone, 475, 481 4-Methylcarbostyril, 855 p-Methylcinnamic acid, 719 4-Methylcoumarin, 853, 854 Methyl crotonate, 926, 927 Methylethylacetic acid, 354, 358 Methylethylethynyl carbinol, 468 Methyl ethyl ketone, 335, 336 purification of, 172 Methyl n-hexyl ether, 314 Methyl n-hexyl ketone, 335, 336 Methyl n-hexyl ketoxime, 348 Methyl hydrogen adipate, 938 Methyl hydrogen sebacate, 938,939 4-Methyl-7-hydroxycoumarin, 834 Methyl iodide, 287 Methyl isopropyl carbinol, 247,255 Methyl 4-keto-octanoate, 936... 

Purification. Small amounts of reaction by-products are produced during the liquid-phase oxidation of toluene. These by-products include acetic and formic acids, benzene, benzaldehyde, benzyl alcohol, aliphatic benzyl esters such as benzyl formate and benzyl acetate, biphenyl, 2-, 3-, and 4-methylbiphenyls, and phthalic acid. Of these only benzaldehyde and benzene [71 -43-2] are currendy separated commercially. 

Basic alumina (13 g) was added to a mixture of methyl 4-formylbenzoate Id (1.00 g, 6 mmol) and acetophenone 2 (0.48 g, 4 mmol) at room temperature. (When the reactants were solid, a minimum amount (2x3 mL) of dichloro-metliane was used to dissolve them prior to the addition of the alumina.) The reaction mixture was then agitated at room temperature for 2.5 h using a Fisher vortex mixer. The product was extracted into dichloromethane (5x15 mL). Removal of the solvent, under reduced pressure, yielded the solid product. Further purification (removal of traces of benzyl alcohol and aldehyde) was carried out by recrystallization from a petroleum ether-ether mixture to afford l-phenyl-3-[4-(carbomethoxy)phenyl]-2-propen-1-one 3d (4-carbomethoxychalcone), mp 119— 120 °C (81%). 

Hydrolysis of the protected alcohol group in 19 is realized by reaction of aqueous sodium hydroxide in iV.iV-dimethylformamide at room temperature and under argon. Chromatographic purification affords the benzylic alcohol derivative 20 in 65% yield (Scheme 9.15). 

The same chemical route was further exploited by dispensing monomer set M3 (0.4 mmol) into seven reactors and treating it with PS-supported 8.50 (0.4 mmol) to give in situ polymer-bound sulfonylpyridinium chlorides 8.51. After stirring at rt for 30 min, stock solutions of dibenzylamine (theoretically 0.25 mmol), prepared as in LIO from benzyl alcohol and benzylamine with >90% yield and purity, were added and stirred at rt (TLC monitoring) for 30-60 min (Fig. 8.28). After the usual work-up and purification, reasonably pure sulfonamides Lll (>90%, HPLC-MS and NMR) were recovered. 

Benzyl alcohol from Fisher Scientific Company was used without further purification. 

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