Alcohols, primary with carbon tetrachloride

Both tert-butyl hypochlorite and N-chlorosuccinimide dehydrogenate primary benzylic alcohols to the aldehydes (equation 213), whereas primary aliphatic alcohols are converted into esters of the corresponding acids [709]. Butyl alcohol dissolved in carbon tetrachloride and treated with tert-butyl hypochlorite in the presence of pyridine at 40-45 C gives, after 2 h, a 66% yield of butyl butyrate [709]. 

The use of polymer-bound triphenylphosphine has also been described in combination with carbon tetrachloride for the condensation of carboxyhc acids with primary amines to give amides via the corresponding in situ formed mixed phosphinic anhydride, and for the conversion of aliphatic alcohols to the corresponding alkyl chlorides [38]. 

Triphenylphosphine in refluxing carbon tetrachloride converts primary and secondary alcohols into the corresponding chlorides under very mild conditions (/) with inversion of configuration (2, J). A suggested route for the transformation is shown. 

That is, the reaction of primary alcohols or ethers with a calculated amount of BTMA Br3 in carbon tetrachloride-water in the presence of Na2HP04 at 60°C gave dimeric esters in good yields. In the case of benzyl alcohol, the only oxidation product was benzaldehyde (Fig. 20). 

The solvent selected must be dry and transparent in the region of interest. When the entire spectrum is of interest, several solvents must be used. A common pair of solvents is carbon tetrachloride (CC14) and carbon disulfide (CS2). Carbon tetrachloride is relatively free of absorption at frequencies above 1333 cm-1, whereas CS2 shows little absorption below 1333 cm-1. Solvent and solute combinations that react must be avoided. For example, CS2 cannot be used as a solvent for primary or secondary amines. Amino alcohols react slowly with CS2 and CC14. 

Berman, E., House, D.E., Allis, J.W. Simmons, J.E. (1992) Hepatotoxic interactions of ethanol with allyl alcohol or carbon tetrachloride in rats. J. Toxicol, environ. Health, 31, 161-176 Bermudez, E., Mirsalis, J.C. Eales. H.C. (1982) Detection of DNA damage in primary cultures... 

CH2OH - —CHiCN.1 This transformation is possible by treatment of a primary alcohol with tri-n-butylphosphine, carbon tetrachloride, potassium cyanide, and 18-crown-6 at room temperature. No reaction occurs in the absence of the crown ether. Yields of nitriles are 70-85%. 

Oxidation of primary and secondary alcohols to carbonyl compounds, Treatment of dimethyl sulfide in carbon tetrachloride at 0° with 1 eq. of chlorine in the same solvent results in rapid formation of the partially insoluble complex (I). This complex has been used by Corey and Kim for oxidation of primary and secondary alcohols. In a typical... 

Sodium ruthenate, Na2Ru04, is prepared in situ from ruthenium tetroxide (in solution in carbon tetrachloride) and 1 M sodium hydroxide by shaking for 2 h at room temperature. The reagent remains in the aqueous layer, which acquires bright-orange color [937]. It oxidizes primary alcohols to carboxylic acids and secondary alcohols to ketones and is comparable with but stronger than potassium ferrate [937]. 

Carbon tetrachloride, CCI4, in the presence of potassium hydroxide at 25-80 °C, transforms primary alcohols into carboxylic acids, methyl ketones into acids with the same number of carbons or with one less carbon in the chain, and aryl methyl sulfones into arenesulfonic acids [954]. 

A very simple and gentle oxidation of primary alcohols to aldehydes is their treatment in chloroform or carbon tetrachloride with a solution of dinitrogen tetroxide, obtained either commercially or by thermal decomposition of lead nitrate. The reaction is carried out at 0 °C through room temperature and gives high yields (91-98%) of benzaldehydes (equation 206) [454]. 

Hypochlorites are very good oxidizers of alcohols and are frequently selective enough to oxidize secondary alcohols in preference to primary alcohols see equations 288-291). Solutions of sodium hypochlorite in acetic acid react exothermically with secondary alcohols within minutes [693]. Calcium hypochlorite in the presence of an ion exchanger (IRA 900) oxidizes secondary alcohols at room temperature in yields of 60-98% [76 5]. Tetrabutylammonium hypochlorite, prepared in situ from 10% aqueous sodium hypochlorite and a 5% dichloromethane solution of tetrabutylammonium bisulfate, oxidizes 9-fluorenol to fluorenone in 92% yield and benzhydrol to benzophenone in 82% yield at room temperature in 35 and 150 min, respectively [692]. Cyclohexanol is oxidized to cyclohexanone by teit-butyl hypochlorite in carbon tetrachloride in the presence of pyridine. The exothermic reaction must be carried out with due precautions [709]. 

Of the compounds we have dealt with so far, alcohols also dissolve in sulfuric acid. Alcohols can be distinguished from alkenes, however, by the fact that alcohols give a negative test with bromine in carbon tetrachloride and a negative Baeyer test—so long as we are not misled by impurities. Primary and secondary alcohols are oxidized by chromic anhydride, CrOa, in aqueous sulfuric acid within two seconds, the clear orange solution turns blue-green and becomes opaque. 

Besides ruthenium tetroxide, other ruthenium salts, such as ruthenium trichloride hydrate, may be used for oxidation of carbon-carbon double bonds. Addition of acetonitrile as a cosolvent to the carbon tetrachloride-water biphase system markedly improves the effectiveness and reliability of ruthenium-catalyzed oxidations. For example, RuCl3 H20 in conjunction with NaI04 in acetonitrile-CCl4-H20 oxidizes (Ej-S-decene to pentanoic acid in 88% yield. Ruthenium salts may also be employed for oxidations of primary alcohols to carboxylic acids, secondary alcohols to ketones, and 1,2-diols to carboxylic acids under mild conditions at room temperature, as exemplified below. However, in the absence of such readily oxidized functional groups, even aromatic rings are oxidized. 

Primary and secondary alcohols are converted into nitriles on refluxing with triphenylphosphine, carbon tetrachloride, DMSO, and sodium cyanide.6 Thus a... 

Crystals. A trihydrate and a sesquibydrate have been obtained. The anhydr form exists in two cryst modifications. Usually long, fine, blunt-ended needles from water + butanol. After dryiug in vacuo over P20, and then at 55-60 in high vacuum mp 204-205 (with decompn, open capillary in block preheated to 200 ). [ojj +316 (c — 0.88). pK in water at 5° — 2.83 at 25 — 2.87. Very sol in water, in isotonic sodium chloride soln and in glucose solns also sol in alcohol, but is inactivated by this solvent, likewise by glycerol and other primary alcohols insol in benzene, carbon tetrachloride, liquid petrolatum. 

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