Diphenylamine reaction, benzyl

Similarly, reactions which are substantially enhanced by the use of PTC can be carried out even with reduced use of PTC with substantial enhanced rates of reaction as has been demonstrated by Sivakumar and Pandit (2000) in the case of conversion of benzamide to benzonitrile. In the case of A-alkylation of diphenylamine with benzyl bromide, in the presence of KOH as the anion source and PEG methyl ether as the PTC, some improvement in the rate has been observed. (Cains et al., 1998). Metal catalysed hydrogenations, such as those based on Ni, Pd/C, and Ru/C also benefit from ultra-sound. 

The reaction of 113 with several Af-lithioamines was investigated and the results are summarized in Table 5. Af-Methylaniline, p-chloro-Af-methylaniline and Af-benzyl-p-anisidine gave 60-67% yield of the desired Af-cyclopropyl arylamines. Diphenylamine gave the desired product however, the yield was not satisfactory. Interestingly, dibenzy-lamine did not afford the desired product at all. This result indicated that the magnesium cyclopropylidene (113) only reacts with Af-lithio arylamines. The reaction of 113 with Af-lithio nitrogen-containing heterocyclic compounds was also studied. From the results shown in Table 5, the yields of the reaction are variable as a function of the heterocyclic compounds used. 

The Hammett p values for the YN2 reaction between diphenylamine and para-substituted benzyl bromides in methanol decrease from 0.64 to 0.10 as the reaction... 

As far as the reaction mechanism is concerned, the formation of alkyl hydroperoxides suggests alkyl radicals as intermediates. Indeed, when cyclohexylbenzene is used, we observe oxygen insertion not only at the benzylic carbon (1 position) but also at the 2 and 4 positions of the cyclohexyl ring. These products may result if a peroxy radical at the 1 position abstracts a hydrogen atom from the sterically favored 2 or 4 position forming another carbon radical capable of reacting further with oxygen. Further support for the presence of a carbon radical is the classical inhibition pattern observed upon addition of the free radical inhibitor diphenylamine. 

Stabilizers UVA 2(2 -hydroxy-5-methylphenyl)benzotriazole Screener carbon black HAS bis(1,2,2,6,6-pentamethyl-4-piperidinyl)-2-n-butyl-2-( 3,5-di-tert-bulyl-4-hydroxy-benzyl) malonate Phenolic antioxidants phenol, 4-methyl-, reaction products with dlcyclopentadiene and isobutene 2,6,-di-tert-butyl-4-(4,6-bis(octylthio)-1,3,5,-triazine-2-ylamino) phenol 2- (1,1 -dimethylethyl)-6-[[3-(1,1 -dimethylethyl)-2-hydroxy-5-methylphenyl] methyl-4-methylphenyl acrylate isotridecyl- 3- (3,5-di-tert-biAyl-4-hydroxyphenyl) propionate 3,5-bis(1,1-dimethyethyl)-4-hydroxy-benzenepropanoic acid. Cl 3-15 alkyl esters 2,2 -isobutylidenebis(2,4 imethylphenol) Amine nonylated diphenylamine Thiosynergist 2,2 -thiobis(6-tert-butyl-4-methylphenol) 4,6-bis(octylthiomethyl)-o-cresol ... 

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