Benzil-benzylic acid

Rearrangement of benzil to benzylic acid via aryl migration. 

Keywords benzil, alkyli metal hydroxide, benzylic acid rearrangement, benzylic acid... 

Tropine Benzylate. endo- -Hytlroxv-O -phenyiben-zeneacetlc acid 8-methyi-8-azahicyeio[3. 2. lfoet-3-yI ester IaH,5aH-tropan-3a -ol benzilate benzitic acid 3o -tropanyl ester glykin BAT BTE BETE. CjjHjjNOj mol wt 351.43. C 75.18%. H 7.17%. N 3.99%. O 13.66%. Prepn Hromatka et al. Monatsh. 83, ]321 (1952). 

Base-induced rearrangement of benzil to benzylic acid via phenyl group migration. More commonly perceived to include the migrations of other groups in a-dicarbonyl compounds ... 

This is a classic benzylic acid rearrangement, and the reaction proceeds just as it does for benzil-the fact that the two rings are bonded makes no difference ... 

The procedure described is essentially that of Ballard and Dehn.1 Stilbene has also been prepared by reduction of desoxy-benzoin,20 benzaldehyde,23 and benzil 2o-2c by dehydrogenation of ethyl benzene,30 toluene,30- 33- 3, and bibenzyl 33-3alkaline reduction of phenylnitromethane,40 phenylnitroacetonitrile,40 and desoxybenzoin 43 by distillation of benzyl sulfone,50 benzyl sulfide,60-63 calcium cinnamate,5 cinnamic acid,5d phenyl cinna-mate,6e-6/ and diphenyl fumarate ie by dehydrohalogenation of a,a -dichlorobibenzyl60 and benzyl chloride 63 by dehalogenation of a,a,c/,a -tetrachlorobibenzyl70 and benzal chloride 73 by the coupling of cinnamic acid and phenyldiazonium chloride 8 by de-... 

A similar mechanism can be written for the formation of phenyl acetone in an irradiated aqueous solution of biacetyl and phenylacetic acid.55 Abstraction of a benzilic hydrogen from phenylacetic acid by a photoexcited biacetyl would produce 3 and a benzylic radical which can add to a second biacetyl molecule. Cleavage of this intermediate would yield a jS-keto acid which, on... 

Recently a complete product study has been carried out for benzil irradiated in cyclohexane.63 A complex mixture containing benzaldehyde, phenyl-cyclohexyl ketone, benzoin benzoate, benzoin, benzoic acid, and smaller amounts of other compounds containing from three to six benzyl groups was obtained. 

Reaction of carboxylate ion with nitrophenyl sulfites gives the carboxylate />-nitrophenyl esters. If the y>-nitrophenyl sulfite is unsymmetncal (02NC6H40S(0)0R, where R is ethyl or phenyl), carboxylate attacks the/>-nitrophenyl side (69). Some amino acids react with methyl and benzyl sulfites in the presence of y>-toluenesulfonic acid to give methyl and benzyl esters of the amino acids as />-toluenesulfonate salts (70). With alcohols, the conversion of benzil to a monoacetal upon addition of sulfuric acid to the benzil in methanol and dimethyl sulfite proceeds in high yield (71). 

Also included in Expt 8.44, is the preparation of 2,3-diphenylquinoxaline (114) and 3-benzyl-2-oxo-l,2-dihydroquinoxaline (115) from o-phenylenediamine and benzil or phenylpyruvic acid respectively. 

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