Benzyl chloride preparation

Reactions specific to sym-trinitrobenzene Addition compounds Preparation of sym-trinitrobenzene Direct nitration of m-dinitrobenzene Preparation from a-trinitrotoluenc Preparation from picryl chloride Preparation from benzyl chloride Preparation from m-xylene Other preparatory reactions... 

In the following preparation, the oxidation of benzyl chloride instead of toluene is therefore given in order to reduce the time required. It should be borne in mind, however, that the procedure is othenvise independent of the nature of the side chain. 

Thiourea. Boil in ethanolic solution with benzyl chloride to prepare the crystalline benzylthiouronium chloride, m.p. lyo i 74" (P- 126). 

By-products are formed in both preparations thus in the former, anthracene, and o- and p-dibenzylbenzenes are present in the fraction of high boiling point. Diphenylmethane is more conveniently obtained by the interaction of benzyl chloride and benzene in the presence of aluminium amalgam ... 

Prepare a solution of benzyl magnesium chloride in a 2-litre three-necked flask from 24-3 g. of magnesium turnings, 600 ml. of sodium-dried ether and 126-5 g. (115 ml.) of redistilled benzyl chloride follow the experimental details given under n-Propylbenzene (Section IV,7). Cool the flask in running water or in ice water. Place a solution of 456 g. of n-butyl-p-toluenesulphonate (Section IV,198) in about twice its volume of anhydrous ether in the dropping funnel, and add it slowly with stirring, at such a rate that the ether just boils a white solid soon forms. The addition is complete after about 2 hours. Pour the reaction product... 

The benzyl chloride quaternary salts RR R"NC3HsCH2 +Cl are prepared similarly 3 g. of redistilled benzyl chloride replaces the methyl p-toluenesulphonate. 

Preparation of benzyl cyanide. Place 100 g. of powdered, technical sodium cyanide (97-98 per cent. NaCN) (CAUTION) and 90 ml. of water in a 1 litre round-bottomed flask provided with a reflux condenser. Warm on a water bath until the sodium cyanide dissolves. Add, by means of a separatory funnel fitted into the top of the condenser with a grooved cork, a solution of 200 g. (181-5 ml.) of benzyl chloride (Section IV.22) in 200 g. of rectified spirit during 30-45 minutes. Heat the mixture in a water bath for 4 hours, cool, and filter off the precipitated sodium chloride with suction wash with a little alcohol. Distil off as much as possible of the alcohol on a water bath (wrap the flask in a cloth) (Fig. II, 13, 3). Cool the residual liquid, filter if necessary, and separate the layer of crude benzyl cyanide. (Sometimes it is advantageous to extract the nitrile with ether or benzene.) Dry over a little anhydrous magnesium sulphate, and distil under diminished pressure from a Claisen flask, preferably with a fractionating side arm (Figs. II, 24, 2-5). Collect the benzyl cyanide at 102-103°/10 mm. The yield is 160 g. 

A suspension of di1Ithiopropyne in THF and hexane was prepared from 0.25 mol of propyne (see Chapter II, Exp. 17). The suspension was cooled to -10°C and 0.22 mol of benzyl chloride was added dropwise in 30 min, while maintaining the temperature of the mixture at about -10°C. The cooling bath was then removed temporarily and the temperature was allowed to rise to After stirring for... 

Substituted aroyl- and heteroaroyltrimethylsilanes (acylsilanes) are prepared by the coupling of an aroyl chloride with (Me3Si)2 without decarbonylation, and this chemistry is treated in Section 1.2[629], Under certain conditions, aroyl chlorides react with disilanes after decarbonylation. Thus the reaction of aroyl chlorides with disilane via decarbonylation is a good preparative method for aromatic silicon compounds. As an interesting application, trimel-litic anhydride chloride (764) reacts with dichlorotetramethyidisilane to afford 4-chlorodimethylsilylphthalic anhydride (765), which is converted into 766 and used for polymerization[630]. When the reaction is carried out in a non-polar solvent, biphthalic anhydride (767) is formed[631]. Benzylchlorodimethylsilane (768) is obtained by the coupling of benzyl chloride with dichlorotetramethyl-disilane[632,633]. 

Secondary and tertiary alkyl halides are not suitable because they react with alkox ide bases by E2 elimination rather than by 8 2 substitution Whether the alkoxide base IS primary secondary or tertiary is much less important than the nature of the alkyl halide Thus benzyl isopropyl ether is prepared m high yield from benzyl chloride a pri mary chloride that is incapable of undergoing elimination and sodium isopropoxide... 

A wide variety of quaternaries can be prepared. Alkylation with benzyl chloride may produce quaternaries that are biologically active, namely, bactericides, germicides, or algaecides. Reaction of a tertiary amine with chloroacetic acid produces an amphoteric compound, a betaine. 

Ben /ben ate [120-51-4] CgH COOCH2CgH, mp, 21°C, cff , 1.118 bp, 323—324°C at 101.3 kPa , 1.5681. This is a colorless, oily liquid with a faiat, pleasant aromatic odor and a sharp, burning taste. It occurs naturally iu Pern and Tolu balsams, is spariugly volatile with steam, and is iusoluble iu water. Benzyl benzoate is prepared commercially by the direct esterification of benzoic acid and benzyl alcohol or by reaction of benzyl chloride and sodium benzoate. The pleasant odor of benzyl benzoate, like other benzoic esters, has long been utilized iu the perfume iadustry, where it is employed as a solvent for synthetic musks and as a fixative. It has also been used iu confectionery and chewing gum flavors. 

The ring-chiorinated benzyl chlorides are used ia the preparation of quaternary ammonium salts and as iatermediates for pharmaceuticals and pesticides. p-C. orohen zyl chloride is an iatermediate ia the manufacture of the rice herbicide, Saturn ((S-4-chlorobenzyl)-N,N-diethylthiolcarbamate [28249-77-6] (75). The o- and -chlorobenzal chlorides (l-chloro-2-and 4-dich1 oromethylhenzenes) are starting materials for the manufacture of o- and p- chlo rob enz aldehyde s. 

N-Alkylations, especially of oxo-di- and tetra-hydro derivatives, e.g. (28)->(29), have been carried out readily using a variety of reagents such as (usual) alkyl halide/alkali, alkyl sulfate/alkali, alkyl halide, tosylate or sulfate/NaH, trialkyloxonium fluoroborate and other Meerwein-type reagents, alcohols/DCCI, diazoalkanes, alkyl carbonates, oxalates or malon-ates, oxosulfonium ylides, DMF dimethyl acetal, and triethyl orthoformate/AcjO. Also used have been alkyl halide/lithium diisopropylamide and in one case benzyl chloride on the thallium derivative. In neutral conditions 8-alkylation is observed and preparation of some 8-nucleosides has also been reported (78JOC828, 77JOC997, 72JOC3975, 72JOC3980). 

The 2,4,6-trimethylbenzyl ester has been prepared from an amino acid and the benzyl chloride (Et3N, DMF, 25°, 12 h, 60-80% yield) it is cleaved by acidic hydrolysis (CF COOH, 25°, 60 min, 60-90% yield 2 N HBr/HOAc, 25°, 60 min, 80-95% yield) and by hydrogenolysis. It is stable to methanolic hydrogen chloride used to remove A-o-nitrophenylsulfenyl groups or triphenylmethyl esters. ... 

The catalyst, 3-benzyl-5-(2-hydroxyethyl )-4-methyl-l, 3-thiazoHum chloride, is supplied by Fluka AG, Buchs, Switzerland, and by Tridom Chemical, Inc., Hauppauge, New York. The thiazolium salt may also be prepared as described below by benzylation of 5-(2-hydroxyethyl)-4-methyl-l,3-thiazole which is commercially available from E. Merck, Darmstadt, West Germany, and Columbia Organic Chemicals Co., Inc., Columbia, SC. The acetonitrile used by the checkers was dried over Linde 3A molecular sieves and distilled under nitrogen, bp 77-78°C. The same yield of thiazolium salt was obtained by the checkers when benzyl chloride and acetonitrile from commercial sources were used without purification. 

Diphenylmethane has been prepared with aluminum chloride as a catalyst from methylene chloride and benzene, from chloroform and benzene as a by-product in the preparation of triphenylmethane, and from benzyl chloride and benzene. It has been prepared by the reduction of benzophenone with hydriodic acid and phosphorus, or with sodium and alcohol. It has also been made by heating a solution of benzyl chloride in benzene with zinc dust, or with zinc chloride. The above method is only a slight modification of the original method of Hirst and Cohen. ... 

Tribromobenzoic acid has been prepared by the deamination of 2,4,6-tribromo-3-aminobenzoic acid (reagents not specified), by hydrolysis of 2,4,6-tribromobenzonitrile, " and by oxidation of the tribromotoluene, the benzyl chloride, the aldehyde,and the glyoxylic acid.i The present method is a modification of that of Bunnett, Robison, and Pennington.i ... 

Both methyltriethylphosphonium fluoride and methyltributylphospho-nium fluoride have been prepared The latter generates benzyl fluoride from benzyl chloride in 80% yield and ethyl fluoroacetate from ethyl bromoacetate in 53% yield Methyltnbutylphosphonium fluoride converts 1-bromododecane to a 50 50 mixture of 1-fluorododecane and 1-dodecene Methyltnbutylphosphonium fluoride also quantitatively forms styrene from 1-bromo-1-phenylethane [26] Methyl-tnbutylphosphonium fluonde is the reagent of choice for the conversion of N,N dimethylchloroacetamide to its fluoride, but it is not able to convert chloro-acetonitnle to fluoroacetomtrile Methyltnbutylphosphonium fluoride changes chloromethyl octyl ether to the crude fluoromethyl ether in 66% yield The stereoselectivity of methyltnbutylphosphonium fluoride is illustrated by the reac tions of the 2-tert-butyl-3-chlorooxiranes [27] (Table 2)... 

Hydrocinnamic Acid.—The preparation illustrates the use of sodium amalgam as a reducing agent It should be noted that hydiocinnamic acid may be also obtained from m.donic ester by acting upon the sodium compound nith benzyl chloride, then hydrolysing and removing carbon dioxide,... 

The quaternary phosphonium salt is prepared by refluxing for 12 hours or longer a mixture of 4.5 g of benzyl chloride and 13 g of triphenylphosphine in 70 ml of xylene. On cooling to approx. 60°, colorless crystals of benzyltriphenylphosphonium chloride can be filtered off, washed with xylene (approx. 50 ml) and dried. The yield is virtually quantitative, mp 310-311°. 

It is prepared artificially, for use as a synthetic perfume, by several methods, for example, by heating benzyl chloride with oxide of lead to 100", or by heating benzyl chloride with potassium acetate and saponifying the benzyl acetate so formed, with caustic potash. 

Benzyl Ginnamate.—The cinnamic acid ester of benzyl alcohol is a natural constituent of storax, tolu, and Peru balsams. It is a crystalline Bubstance with a characteristic sweet balsamic odour. It may be prepared by heating sodium cinnamate, alcohol, and benzyl chloride together under a reflux condenser. It is a useful ester where a sweet balsamic odour is required to be introduced into a perfume, especially cf the heavy type. It forms white, glistening prisms, which melt at 39°, and.decompose when heated to 350°. The best commercial specimens have the following characters —... 

Benzylacetophenone has been prepared by the reduction of benzalacetophenone with zinc and acetic acid1 and catalytic-ally with palladium and hydrogen 2 by the reduction of /3-duplo-benzylidene acetophenone monosulfide 3 by the oxidation of the corresponding car bind with chromic acid 4 by the hydrolysis of ethyl benzyl benzoylacetate 5 from acetophenone and benzyl chloride by the action of sodamide 6 and from benzoic and hydrocinnamic adds using as catalysts manganese oxide 7 and ferric oxide.8... 

Fleischer1 prepared benzylaniline by heating aniline with benzyl chloride at i6o°. This reaction may be very violent and always leads to mixtures. Bernthsen and Trompetter 2 reduced thiobenzanilide with zinc and hydrochloric acid or sodium amalgam, while O. Fischer 3 reduced bcnzalaniline with sodium and alcohol, to benzylaniline. Knoevenagel4 obtained a 32 per cent yield of benzylaniline from benzyl alcohol and aniline in the presence of iodine. Ullmann5 describes the preparation of benzylaniline from benzyl chloride and excess of aniline at low temperatures. 

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