Benzyl alcohol -» toluene

Figure 6 Hydrogenation of benzaldehyde over Ni-monoliihic catalyst 420 K, 16 bar, 1250 RPM. benzaldehyde, + benzyl alcohol, toluene. (From Ref. 28.)...

A series of N-alkyl perfluoroalkanamides were recently prepared by the Weiss group [6]. Perfluorinated alkanoic acids were transformed into acid chlorides by oxalyl chloride in benzene, and subsequent amidation with alky-lamine in benzene gave N-alkyl perfluoroalkanamides (Scheme 1). The amide derivative 3 exhibited efficient gelation (mgc < 2.5 wt %) of various organic solvents including EtOH, 1-butanol, 1-octanol, hexane, -octane, benzyl alcohol, toluene, and CCI4. 

PROBLEM 4.5 Write the formulas for benzyl alcohol, toluene, and benzoic acid (eq. 4.1). 

The white crystalline diazoketone is dissolved in 10 ml of dry chloroform. Hydrogen chloride gas is bubbled slowly for 2 min into the solution that is cooled in ice. A spectrum of the product, 5-chloro-4-oxo-A -benzoxycarbonyl L-[5- C]norvaline-a-benzyl ester, should exhibit no diazo absorption. The chloroform is removed by flash evaporation and the residual material is suspended in 20 ml of 6 Af HCl and heated at 70° for 10 hr. The supernatant solution is decanted and replaced with 20 ml of 6 iV HCl, and the procedure is repeated until no insoluble material remains. The solutions are combined, and the products generated by removal of the protecting groups (benzyl alcohol, toluene) are removed by lyophilization the remaining colorless, moist powder may be dried under reduced pressure over PaO.-,. The net yield of L-2-amino-4-oxo-5-chloropentanoic acid hydrochloride is about 80% (49 mg, 0.24 mmole specific activity 1.16 Ci/mole). The chloroketone hydrochloride can be recrystallized from acetone-water to give the free base m.p. 151°-152° (dec.). 

Purification commercial CbzCl is typically better than 95% pure and is often contaminated by benzyl chloride, benzyl alcohol, toluene, and HCl. On storage it can undergo a slow HCl-catalyzed decomposition, even at low temperature.It has been recommended that CbzCl which has been stored for long periods be purified by flushing with a stream of dry air to remove dissolved CO2 and HCl impurities. Filtration and storage over Na2S04 may be followed by distillation it is important that low temperatures (oil bath <85 °C) and high vacuum be used to minimize thermal decomposition. ... 

It is prepared by the direct chlorination of toluene in the presence of PClj. It is purified by fractionation from the unchanged toluene and the higher chlorinated products. It is used for benzylating amines and for preparing benzyl alcohol. 

Benzyl Chloride. Benzyl chloride is manufactured by high temperature free-radical chlorination of toluene. The yield of benzyl chloride is maximized by use of excess toluene in the feed. More than half of the benzyl chloride produced is converted by butyl benzyl phthalate by reaction with monosodium butyl phthalate. The remainder is hydrolyzed to benzyl alcohol, which is converted to ahphatic esters for use in soaps, perfume, and davors. Benzyl salicylate is used as a sunscreen in lotions and creams. By-product benzal chloride can be converted to benzaldehyde, which is also produced directiy by oxidation of toluene and as a by-product during formation of benzoic acid. By-product ben zotrichl oride is not hydrolyzed to make benzoic acid but is allowed to react with benzoic acid to yield benzoyl chloride. 

The only industrially important processes for the manufacturing of synthetic benzaldehyde involve the hydrolysis of benzal chloride [98-87-3] and the air oxidation of toluene. The hydrolysis of benzal chloride, which is produced by the side-chain chlorination of toluene, is the older of the two processes. It is no longer utilized ia the United States. Other processes, including the oxidation of benzyl alcohol, the reduction of benzoyl chloride, and the reaction of carbon monoxide and benzene, have been utilized ia the past, but they no longer have any iadustrial appHcation. 

In the past benzal and benzyl chlorides were co-produced for the manufacture of benzaldehyde and benzyl alcohol, but today the vast majority of the benzaldehyde produced from benzal chloride is that which is made from recovered (by-product) material. For an historical article regarding the chlorination of toluene and the subsequent production of benzaldehyde, benzyl alcohol, and benzoic acid, see reference 4. 

Manufacture. Today benzyl alcohol is almost universally manufactured from toluene which is first chlorinated to give benzyl chloride [100-44-7]. This is then hydrolyzed to benzyl alcohol by treatment with aqueous sodium carbonate. 

In the future it may be possible to oxidize toluene microbiaHy to produce benzyl alcohol. Treatment of toluene in the presence of air with a culture of Af. thermophila in a phosphate buffer is reported to yield a mixture of benzaldehyde, benzyl alcohol, and -cresol [106-44-5] (3). 

Water with aniline, benzene, benzyl alcohol, carbon disulfide, carbon tetrachloride, chloroform, cyclohexane, cyclohexanol, cyclohexanone, diethyl ether, ethyl acetate, isoamyl alcohol, methyl ethyl ketone, nitromethane, tributyl phosphate or toluene. 

Benzyioxycarbonyi chioride (Cbz-Ci, benzyi cbioroformate) [501-53-1] M 170.6, b 103 /20mm, d 1.195, n 1.5190. Commercial material is better than 95% pure and may contain some toluene, benzyl alcohol, benzyl chloride and HCl. After long storage (e.g. two years at 4 , Greenstein and Winitz [The Chemistry of the Amino Acids Voi 2 p. 890, J Wiley and Sons NY, 1961] recommended that the liquid should be flushed with a stream of dry air, filtered and stored over sodium sulfate to remove CO2 and HCl which are formed by decomposition. It may further be distilled from an oil bath at a temperature below 85 because Thiel and Dent [Annalen 301 257 1898] stated that benzyioxycarbonyi chloride decarboxylates to benzyl chloride slowly at 100 and vigorously at 155 . Redistillation at higher vac below 85 yields material which shows no other peaks than those of benzyioxycarbonyi chloride by NMR spectroscopy. LACHRYMATORY and TOXIC. 

Carbocations can also be generated during the electrolysis, and they give rise to alcohols and alkenes. The carbocations are presumably formed by an oxidation of the radical at the electrode before it reacts or diffuses into solution. For example, an investigation of the electrolysis of phenylacetic acid in methanol has led to the identification of benzyl methyl ether (30%), toluene (1%), benzaldehyde dimethylacetal (1%), methyl phenylacetate (6%), and benzyl alcohol (5%), in addition to the coupling product bibenzyl (26%). ... 

Oxidizing toluene to benzaldehyde is a catalyzed reaction in which a selective catalyst limits further oxidation to benzoic acid. In the first step, benzyl alcohol is formed and then oxidized to benzaldehyde. Further oxidation produces benzoic acid ... 

A sample of polyester (ca. 1 g, exactly weighed) is dissolved in 20 mL toluene-ethanol mixture (1/1 vol.) and titrated by a solution of KOH in ethanol (0.05 mol/L) using a potentiometric titrator. A blank titration must be performed under the same conditions. Hardly soluble polyesters (e.g., PET) must be dissolved in an o-cresol-chloroform mixture or in hot benzyl alcohol.417 The result (acid content) is normally expressed in mmol COOH/g polyester but may also be given as the acid number, defined as the number of milligrams of KOH required to neutralize 1 g of polyester. [Acid number = (number of mmol COOH/g polyester) x 56.106.]... 

By small-angle neutron scattering experiments on water/AOT/hydrocarbon microemulsions containing various additives, the change of the radius of the miceUar core with the addition of small quantities of additives has been investigated. The results are consistent with a model in which amphiphilic molecules such as benzyl alcohol and octanol are preferentially adsorbed into the water/surfactant interfacial region, decreasing the micellar radius, whereas toluene remains predominantly in the bulk hydrocarbon phase. The effect of n-alcohols on the stability of microemulsions has also been reported [119],... 

Dehydration reactions catalysed by NHC complexes have been reported where a new C-C bond is formed. Peris has used [Ir(OTf)2Cp (NHC)] complexes including compound 35 to benzylate arenes with alcohols and other reagents [14]. For example, the dehydrative C-C coupling of benzyl alcohol 8 with toluene 33 is catalysed by 0.1 mol% of 35 to give a mixture of benzylated products 34 (Scheme 11.8). 

Yamato (1995) has given an extensive coverage of a variety of reactions such as alkylation of benzene, condensation of benzene/toluene with benzyl alcohol, and condensation of benzoyl chloride with benzene/toluene using Nafion resin. 

The availability of Nafion on silica has not only lowered the cost of the resin but also has made it versatile (Sun et al., 1997 Harmer et al., 1998). A number of industrially important reactions have been attempted, with considerable success, with these catalysts. Consider the Fries rearrangement of phenyl acetate to p-acetyl phenol (/t-hydroxy acetophenone). This has been accomplished by Hoelderich and co-workers (Heidekum, 1998). In the ca.se of alkylation of benzene with benzyl alcohol, Amberlyst-15 and p-toluene sulphonic acid are ineffective and Nafion on silica works well at 80 °C. 

In earlier work, Bhaumik and Kumar (1995) have reported that the use of two liquid phases in the oxidation of hydrophobic organic substances with aqueous H2O2 using titanium silicate as the catalyst not only enhances the rate of oxidation but also improves selectivity for species like toluene, anisole, and benzyl alcohol. For a single liquid phase acetonitrile was u.sed a solvent. The solid-liquid system gives high ortho selectivity. Thus, in the case of anisole the ratios of o to p for. solid-liquid and solid-liquid-liquid system were 2.22 1 and 0.35 1, respectively. 

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