Alcohols, analysis benzyl

As could have been seen from an analysis of the product during the course of the reaction, only the hydrodechlorination of 3c took place. No other possible dehalogenated products, e.g., benzyl alcohol or benzyl ethyl ether, were detected. This might explain why, particularly in the case of catalyst Pd 1C, the chlorosubstituted benzyl ether (4b) was the only product formed in high yield. Because of the kind and strength of acidity,... 

This experiment describes a characterization analysis in which the degree of association, equilibrium constant, and hydrogen bond energy are measured for benzyl alcohol and phenol in CCI4. 

This method is particularly applicable to the more reactive benzyl halides which are easily hydrolyzed in the aqueous media usually employed for the metathetical reaction with alkali cyanides. For example, anisyl chloride treated with sodium cyanide in aqueous dioxane gives, as a by-product, 5-10% of anisyl alcohol as determined by infrared analysis. The use of anhydrous acetone not only prevents hydrolysis to the alcohol but also decreases the formation of isonitriles. This method was also applied successfully by the submitters to the preparation of -chlo-rophenylacetonitrile in 74% yield. 

Benzyl cyanide, C Hj. CH.,CN, or phenyl-aceto-nitrile, is a constituent of cress oil, and probably of neroli oil. It is a strong smelling liquid boiling at 231 5°, and having a specific gravity 1 0146 at 18°. On boiling with alcoholic potash it yields phenyl-acetic acid, which can be identified by its melting-point, 77°, and by the analysis of its silver salt. 

A number of recommendations have been made in the development of quantitative chromatographic methods. The American Society for Testing Materials — using as a benchmark the reversed phase separation of benzyl alcohol, acetophenone, benzaldehyde, benzene, and dimethylterephthalate — discovered substantial laboratory-to-laboratory differences in quantitative analysis.53 These compounds are routinely used to test column performance or for system suitability testing. A followup study, using benzyl alcohol, acetophenone, p-tolualdehyde, and anisole, showed that measurement of... 

Improved control was observed, however, upon addition of benzyl alcohol to the dinuclear complexes.887 X-ray crystallography revealed that whereas (296) simply binds the alcohol, (297) reacts to form a trinuclear species bearing four terminal alkoxides. The resultant cluster, (298), polymerizes rac-LA in a relatively controlled manner (Mw/Mn=1.15) up to 70% conversion thereafter GPC traces become bimodal as transesterification becomes increasingly prevalent. NMR spectroscopy demonstrates that the PLA bears BnO end-groups and the number of active sites was determined to be 2.5 0.2. When CL is initiated by (298) only 1.5 alkoxides are active and kinetic analysis suggests that the propagation mechanisms for the two monomers are different, the rate law being first order in LA, but zero order in CL. 

TiCU readily functionalizes hydrophilic polymers such as poly(vinyl alcohol), m-ciesol novolac and methacrylic acid copolymers as well as moderately hydrophobic polymers such as poly(methyl methacrylate), poly(vinyl acetate), poly(benzyl methacrylate) and fully acetylated m-cresol novolac. HCI4 did not react with poly(styrene) to form etch resistant films indicating that very hydrophobic films follow a different reaction pathway. RBS analysis revealed that Ti is present only on the surface of hydrophilic and moderately hydrophobic polymer films, whereas it was found diffused through the entire thickness of the poly(styrene) films. The reaction pathways of hydrophilic and hydrophobic polymers with HCI4 are different because TiCl is hydrolysed by the surface water at the hydrophilic polymer surfaces to form an etch resistant T1O2 layer. Lack of such surface water in hydrophobic polymers explains the absence of a surface TiC>2 layer and the poor etching selectivities. 

Stereochemical analysis of the benzylic alcohols formed from both (R)- and (S)-phcnylcthanc-1 -d after incubation with CYP2B4 established a strong cross-over component... 

Analysis of the Benzyl Chloride.—The quantitative determination of halogen in substances containing halogen in aliphatic combination is not carried out in a sealed tube by the Carius method (cf. p. 69), but by hydrolysis with standard alcoholic potassium hydroxide solution. Since this method is very often used, a check on the purity of the present preparation may be combined with practice in this method of analysis. 

The cooled reaction product is treated with 200 cc. of water, the layer of oil separated, washed once with a second portion of water, and subjected to distillation in vacuo. The first fraction of the distillate contains benzyl alcohol together with unchanged aldehyde, as well as a small quantity of water. The temperature then rises rapidly to the boiling-point of benzyl benzoate, when the receivers are changed. The product boils at 184-185°/15 mm., and analysis by saponification shows it to consist of 99 per cent ester. A yield of 410-420 g. is obtained, which corresponds to 90-93 per cent of the theoretical amount. This benzyl benzoate supercools readily, but after solidifying... 

The solids analysis described above can be taken to yet another level by correlating the color measurement to chemical properties. An excellent model system is vanadium pyrophosphate (VPO), which is a well-known catalyst for butane oxidation to maleic anhydride. During the synthesis of the catalyst precursor, solid V2O5 particles are dispersed in a mixture of benzyl alcohol and i-butanol. In this slurry phase, the vanadium is partly reduced. Addition of phosphoric acid leads to a further reduction and the formation of the VPO structure. With a diffuse reflectance (DR) UV-vis probe by Fiberguide Ind., the surface of the suspended solid particles could be monitored during this slurry reaction. Four points can be noted from Figure 4.4 ... 

In Figure 3, the active steroid (triamcinolone acetonide) and preservative (benzyl alcohol) are determined from a steroid cream. The higher molecular weight components of the cream base are well separated from the analytes. The ability to elute all the components of a cream or ointment in a SMGPC analysis gives an important sample preparation advantage over competing separation techniques. 

The enantiomeric purity is determined by chiral stationary phase, supercritical fluid chromatographic (CSP-SFC) analysis (Berger Instruments, Daicel Co. CHIRALCEL OD column 4% methanol, 180 psi, 3.0 mUmin flow rate detection at 220 nm). Racemic 1-phenylpropanol exhibited base-line separation of peaks of equal intensity arising from the R-isomer (tp, 2.74 min) and the S-isomer (tp, 3.10 min) whereas the synthetic alcohol showed these peaks in the ratio 97.7 / 2.3. This chromatographic method allowed for identification of the trace contaminants propiophenone (tp, 1.63 min) and benzyl alcohol (tp 3.40 min). 

Fig. 5.2. Gas chromatography (GC) and electroantennography (EAG) analysis of male Manduca sexta antennal responses to floral volatiles from the night blooming cactus Peniocereus greggii. The upper trace is a flame ionization detection (FID) chromatogram of floral headspace odors separated on a carbowax GC column, while the lower trace is a simultaneous recording of summed antennal action potentials elicited by individual compounds as they elute. The largest absolute responses followed methyl benzoate, methyl salicylate, and benzyl alcohol (peaks 3-5, respectively). Note the poor responses (circled) to benzaldehyde and benzyl benzoate (peaks 2, 6) and the disproportionately higher responses (bold arrows) to methyl salicylate and benzyl salicylate (peak 7) relative to their peak areas. Peak 1 is the internal standard (toluene) remaining unnumbered peaks are ambient contaminants.

The purity of the Dess-Martin periodinane (2) was assayed by treatment of 2 (1 equiv) with an excess of benzyl alcohol (2 equiv) in methylene chloride (CH2CI2) followed by analysis of the reaction mixture for benzaldehyde by capillary vapor phase chromatography (15-m fused silica capillary column, Durawax DX3 stationary phase, 120°C). After correction for response factors, the purity was established to be >95%. 

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