Esters benzyl compounds

Dibenzyl phosphite See other BENZYL compounds, phosphorus esters... 

Chemical Abstracts refers to sulfites as sulfurous acid esters. Simple esters (benzyl, phenyl, ethyl, etc.) are listed as sulfurous acid esters under the names of the corresponding hydroxy compound. All mixed esters are indexed separately under the heading sulfurous acid esters. ... 

Condensation of unsymmetrical hydrazines with 2-chloronicotinic acid derivatives has generally yielded 1-substituted products, but the acid chloride 10a and benzylhydrazine afforded, via the hydrazide lOd, 2-benzyl compound 13.23 The isomer 12 (R = CH2Ph) was obtained either directly from the ester lOe or from 14 via the hydrazide 10c.23... 

NMR spectroscopy) executed. Reaction of iminodiacetic methyl ester also results in the formation of compound 100. These ester derivatives are difficult to hydrolyze in excess mineral acids. The tert-butyl ester of compounds 101 can be hydrolyzed with excess trifhioromethanesulfonic acid. In contrast, by the photoaddition of various glycine esters to C60 only compounds lOOa-c were isolated (Scheme 45). Therefore, the reaction mechanism for the photochemical and the thermal pathway must be different. Again, the reactivity of the glycine esters increases from the benzyl to the methyl ester probably due to steric hindrance. 

Both catalytic and chemical methods are effective for the hydrogenolysis of benzyl ethers. Catalytic methods have found much wider use than the chemical methods, presumably because of the milder conditions that prevail. A general survey of the hydrogenolysis of benzyl compounds (benzyl amines, sulfides, and esters are also subject to hydrogenolysis to varying degrees) has recently been made, and the reader is referred to this discussion for a complete treatment of the scope of the reaction. 

To our knowledge no further information about the environmental persistence and the environmental fate for 4-methoxycinnamic acid 2-ethylhexyl ester, benzyl benzoate, benzophenone, dibenzyl ether and thymol are available. Nevertheless, due to their source specificity, these compounds are appropriate candidates for the application as anthropogenic markers in the case of sufficient persistence. 

In addition numerous compounds were detected which may serve as potential anthropogenic markers with respect to their source specifity and environmental persistence. Plasticizers (alkylsulfonic acid aryl esters, tributyl and tricresyl phosphates), synthetic fragrances (galaxolide, tonalide, 4-oxoisophorone) and additives of personal care products (4-methoxycinnamic acid 2-ethylhexyl ester, benzyl benzoate, dibenzyl ether, benzophenone) occurred due to sewage treatment plant effluents and reflect therefore an anthropogenic contamination of the particulate riverine matter, even in marine systems. 

Evidence for such an additional mechanism also comes from the work of Guo, in the form of the quantum yields for loss of optical activity and for loss of starting material for compounds 157, 158, and 3-CH3 [61]. It is unlikely that the quantum yield for cleavage by methyl p-tolyl sulfoxide is higher than that for the benzyl compound, and that the sulfinyl methyl pair would be so overwhelmingly returned to the sulfoxide, as compared to escape products or sulfenic ester formation. Current evidence does not exist to establish the actual mechanism(s) firmly. 

This product is sufficiently pure for the preparation of phenylacetic acid and its ethyl ester, but it contains some benzyl tso-cyanide and usually develops an appreciable colour on standing. The following procedure removes the iso-cyanide and gives a stable water-white compound. Shake the once-distilled benzyl cyanide vigorously for 5 minutes with an equal volume of warm (60°) 60 per cent, sulphuric acid (prepared by adding 55 ml. of concentrated sulphuric acid to 100 ml. of water). Separate the benzyl cyanide, wash it with an equal volume of sa+urated sodium bicarbonate solution and then with an equal volume of half-saturated sodium chloride solution- Dry with anhydrous magnesium sulphate and distil under reduced pressure. The loss in washing is very small (compare n-Butyl Cyanide, Section 111,113, in which concentrated hydrochloric acid is employed). 

The production of both an alcohol and the sodium salt of an acid might easily be confused with the hydrolysis products of an ester (in the above instance benzyl benzoate). Such an error would soon be discovered (e.g., by reference to the b.p. and other physical properties), but it would lead to an unnecessary expenditure of time and energy. The above example, however, emphasises the importance of conducting the class reactions of neutral oxygen-containing compounds in the proper order, viz., (1) aldehydes and ketones, (2) esters and anhydrides, (3) alcohols, and (4) ethers. 

Substitution of an ester of dithiocarbamic acid such as alkyl or benzyl ester (171), or their salts leads directly to 2-substituted mercaptothiazoles (172) (Scheme 87) (272, 461). Some of these compounds have an antifungal activity (561). 

A problem associated with the use of abrasive metal poHshes is that the fresh metal, which has been exposed by the cleaning, rapidly oxidizes or tarnishes. Thus, many modem poHshes contain inhibitors. Sulfur compounds, eg, alkyl benzyl thiols, commonly are used, as are mercapto esters such as lauryl thioglycolate [3746-39-2] and dialkyldisulfides (52—54). 

Nearly all of the benzyl chloride [100-44-7], henzal chloride [98-87-3], and hen zotrichl oride /P< -(97-i manufactured is converted to other chemical intermediates or products by reactions involving the chlorine substituents of the side chain. Each of the compounds has a single primary use that consumes a large portion of the compound produced. Benzyl chloride is utilized in the manufacture of benzyl butyl phthalate, a vinyl resin plasticizer benzal chloride is hydrolyzed to benzaldehyde hen zotrichl oride is converted to benzoyl chloride. Benzyl chloride is also hydrolyzed to benzyl alcohol, which is used in the photographic industry, in perfumes (as esters), and in peptide synthesis by conversion to benzyl chloroformate [501-53-1] (see Benzyl ALCOHOL AND p-PHENETHYL ALCOHOL CARBONIC AND CARBONOCm ORIDIC ESTERS). 

Nearly all uses and appHcations of benzyl chloride are related to reactions of the active haUde substituent. More than two-thirds of benzyl chloride produced is used in the manufacture of benzyl butyl-phthalate, a plasticizer used extensively in vinyl flooring and other flexible poly(vinyl chloride) uses such as food packaging. Other significant uses are the manufacture of benzyl alcohol [100-51-6] and of benzyl chloride-derived quaternary ammonium compounds, each of which consumes more than 10% of the benzyl chloride produced. Smaller volume uses include the manufacture of benzyl cyanide [140-29-4], benzyl esters such as benzyl acetate [140-11-4], butyrate, cinnamate, and saUcylate, benzylamine [100-46-9], and benzyl dimethyl amine [103-83-8], and -benzylphenol [101-53-1]. In the dye industry benzyl chloride is used as an intermediate in the manufacture of triphenylmethane dyes (qv). First generation derivatives of benzyl chloride are processed further to pharmaceutical, perfume, and flavor products. 

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