Reaction Of Benzoyl Peroxide Research Articles

Aroyl peroxides. Part VI. Reactions of aroyl peroxides with nitrogen dioxide

The products of the decomposition of benzoyl peroxide in carbon tetrachloride in the presence of nitrogen dioxide have been investigated quantitatively, and the mechanism previously suggested has been confirmed. The reaction of benzoyl peroxide with nitrogen dioxide in the absence of solvent has been found to be similar, but less complex. The formation of benzoyl nitrate was indicated by the isolation of a nitration product from reactions in the presence of p-xylene. The decomposition of a series of aroyl peroxides in the presence of nitrogen dioxide gave the corresponding nitro-compounds.

The interaction between polymerization initiators and inhibitors in solution—IV: The reaction of benzoyl peroxide with hydroquinone in solution

The reaction between benzoyl peroxide and hydroquinone in a wide variety of solvents has been investigated by isolation and identification of the products. Benzoic acid, p-benzoquinone and benzoyloxy derivatives of p-benzoquinone are obtained under all conditions. Their relative amounts are largely determined by the molar ratios of the reactants and the nature of the solvent. In strongly polar solvents of high solvation power, p-benzoquinone is formed in preference to its derivatives. Nevertheless, the yield of 2,5-dibenzoyloxy p-benzoquinone reaches a maximum in acrylonitrile. Only in this solvent, at equal molar ratios of reactants, is full substitution in the hydroquinone nucleus achieved with the formation of tetrabenzoyloxy hydroquinone. These facts, together with the partial polymerization of acrylonitrile at room temperature at slightly higher peroxide/hydroquinone ratios and the complete suppression of the polymerization when perchloric acid is added, could be explained by a heterolytic mechanism involving the formation and controlled separation of ion pairs derived from the reactants.

The interaction between polymerization initiators and inhibitors in solution. III. The reaction of benzoyl peroxide with 2,5‐dichloro‐1,4‐benzoquinone and 2,3,5,6‐tetrachloro‐1,4‐benzoquinone (chloranil) in chlorobenzene

AbstractThe reaction of benzoyl peroxide with 2,5‐dichloro‐1,4‐benzoquinone and 2,3,5,6‐tetrachloro‐1,4‐benzoquinone (chloranil) in chlorobenzene was studied by isolation and identification of the reaction products.In dilute solution (0,02 mol peroxide/dm3), both phenyl and benzoyloxy radicals interact with 2,5‐dichloro‐1,4‐benzoquinone to form the corresponding quinonoid derivatives by substitution of hydrogen atoms in the quinone nucleus. Chloranil does not react under these conditions.In concentrated solution (0,5 mol peroxide/dm3), both 2,5‐dichloro‐1,4‐benzoquinone and chloranil are attacked by radicals of the spontaneous as well as the induced decomposition of the peroxide. Aryl radicals (but not benzoyloxy radicals) can substitute only one chlorine atom of the chloranil molecule. The difficulty is due to the steric hindrance of the chlorine atoms and the instability of the radical intermediate. This probably accounts for the tendency of chloranil to react with polymeric radicals through O‐ rather than C‐atoms.

The interaction between polymerization initiators and inhibitors in solutions. 1. The reaction of benzoyl peroxide with p‐benzoquinone in dilute solutions in chlorobenzene

AbstractThe reaction of benzoyl peroxide with p‐benzoquinone in dilute solutions in chlorobenzene was investigated by isolation and identification of some of the reaction products. The reaction is complex; the identified products were phenyl benzoquinone, benzoyloxy benzoquinone, quinhydrone of p‐benzoquinone, benzoic acid, and chlorobiphenyls. There was a considerable amount of tarry quinoid products of unspecific physical properties. Neither simple disubstituted quinoid products, nor mono‐ or di‐ethers of hydroquinone were detected. A mechanism based on these findings has been suggested for the reaction.

Studies on the reaction of benzoyl peroxide with NN-disubstituted aromatic amines and related compounds. VI. Some attempts to effect o-hydroxylation in the strychnine series.

Attempts to protect the carboxy-group of strychnic acid so as to allow hydroxylation in the 4-position by means of dibenzoyl peroxide were unsuccessful. The Wieland–Gumlich aldehyde methyl ether (5) and its 12-epimer reacted with dibenzoyl peroxide to yield the corresponding Nb-oxides. 11-lsonitroso-N-methyl-sec-pseudostrychnine was prepared, but we were unable to convert it into a compound analogous to the Wieland–Gumlich aldehyde.

Reactions of selective cleavage of Ge-Cd bonds of bis-(triethylgermyl) cadmium

1. In the reaction of phenol, acetic and benzoic acids with an equimolar amount of bis(triethylgermyl) cadmium, there is a selective heterolysis of the Ge-Cd-Ge group, and phenoxy- or acyloxy(triethylgermyl) cadmium compounds are formed, respectively. 2. The reaction of benzoyl peroxide with bis(triethylgermyl)- and bis(triphenylgermyl) cadmium leads to selective cleavage of the heteroelement-heteroelement bonds.

The Reactions of Aroyl Peroxides with Grignard Reagents. III. On the Structure and the Reaction of the Complex Containing Benzoyl Peroxide

Abstract The orange-colored complex which is formed in the reaction of benzoyl peroxide with Grignard reagent was studied by infrared spectra, and the reaction of the complex with Grignard reagent was also examined. In this complex, the structure of BPO was still maintained by coordinating with magnesium atom through the peroxidic as well as the carbonyl oxygen atoms. Reaction products of this complex with phenylmagnesium bromide were benzoic acid(as Mg-salts), phenyl benzoate, benzophenone, triphenylcarbionol, and bromobenzene. The heterolytic mechanism on the formation of bromobenzene was proposed. The molar ratio of products depended seriously upon the mode of addition of Grignard reagents. The exclusive formation of bromobenzene and Mg-salts of benzoic acid without phenyl benzoate under an experimental condition was explained by assuming the electron-transfer process through the coordinating bond in the complex.

Studies of Organic Peroxides. XI. The Reaction of Benzoyl Peroxide with Secondary Amines in Binary Mixed Solvents

Abstract The rate constants of the reaction of benzoyl peroxide with some typical secondary amines, namely, diphenylamine, N-methylaniline, and piperidine, were measured in benzene-nitrobenzene binary mixed solvents. The reaction rates of diphenylamine and N-methylaniline are little influenced by the compositions of the solvents, while the reaction of piperidine proceeds more rapidly in nitrobenzene than in benzene. The isokinetic relationship holds for the reaction of piperidine in the binary mixed solvents. The isokinetic temperature is calculated to be 265°K. The analysis of the behavior of these reactions in the mixed solvents leads to the conclusion that, in the cases of diphenylamine and N-methylaniline, there are no specific interactions between the activated complexes and solvent molecules, whereas in the case of piperidine the activated complex is weakly solvated with the polar nitrobenzene. The reaction of benzoyl peroxide with N-methylaniline and N-n-butylaniline was also studied in benzene. These amines have a higher reactivity than would be expected from their basicity. This higher reactivity is probably due to the resonance stabilization of the activated complex besides the formation of a lessionic activated complex.

Studies on the reaction of benzoyl peroxide with NN-disubstituted aromatic amines and related compounds. Part V. Preparation of 5,11-disubstituted 5,6,11,12-tetrahydrophenhomazines from α-diamines

NN′-Dialkyl-NN′-diaryl- and NNN′N′-tetra-aryl-methanediamines, when treated with weak acids in chloroform solution, afford 5,11-disubstituted 5,6,11,12-tetrahydrophenhomazines. The reaction, which is of preparative value, appears to involve decomposition of the α-diamine to give an iminium ion, which then attacks a second molecule of the diamine. In the presence of excess of NN-dimethylaniline the latter is attacked in the para-position by the iminium ion. 1,2,3,4-Tetrahydro-1,6-dimethyl-3-p-tolylquinazoline, when treated with methyl bromide, also yields a phenhomazine of the same type.

Initiation of radical polymerization with N‐acyloxytrialkylammonium tetraphenylborates

AbstractIn order to clarify the initiation mechanism of vinyl polymerization initiated with tertiary amine/acyl peroxide systems and with tertiary amine/acid anhydride systems, some N‐acyloxytrialkylammonium salts, which are known as intermediates in these reactions, were prepared and used as initiators for the polymerization of methyl methacrylate (MMA). N‐benzoyloxytriethylammonium tetraphenylborate was isolated from the reactions of benzoyl peroxide with triethylamine and of benzoic anhydride with triethylamine oxide, in the presence of sodium tetraphenylborate, at low temperature. Similarly N‐benzoyloxytrimethylammonium and N‐toluyloxytrimethylammonium tetraphenylborates were also isolated. All of these salts showed activity as initiator in the polymerization of MMA. From the kinetic study of this polymerization and from the result of copolymerization with styrene, the polymerizations initiated with N‐benzoyloxytriethylammonium tetraphenylborate were found to proceed via a radical mechanism.From the results obtained, it was concluded that the initiation mechanism for vinyl polymerizations with tertiary amine/acyl peroxide and tertiary amine oxide/acid anhydride systems which was proposed previously, is valid, i.e. these reactions proceed via an N‐acyloxytrialkylammonium intermediate which is then capable of a homolytic decomposition of its N⊕–O bond into radicals to initiate the radical polymerization.

Homolytic aromatic substitution. Part XXXIV. Major products from the reaction of benzoyl peroxide with p-disubstituted benzenes

The reaction of benzoyl peroxide with para-disubstituted benzenes (excluding those with sulphur-containing substituents) can lead to substitution by phenyl and/or benzoyloxy-radicals. Product formation is dependent upon the nature of the substituent groups and may be correlated with Hammett σp values. In para-substituted toluenes, the formation of bibenzyls is reduced with increase in the σp value of the para-substituent. Neither phenylation nor benzoyloxylation of the aromatic ring is observed in the reactions of benzoyl peroxide with methyl phenyl sulphide, methyl p-tolyl sulphide, or methyl p-tolyl sulphoxide. The major reaction is oxidation at the sulphur atom, which leads to the formation of, in addition to benzoic anhydride, arylthiomethyl and arylsulphinylmethyl benzoates from the aryl sulphides and sulphoxides respectively. There is no evidence that free radicals are involved in the reaction of benzoyl peroxide with these sulphur-containing compounds.

Homolytic reactions of perfluoroaromatic compounds. Part III. Reactions of benzoyl peroxide with hexafluorobenzene, chloro-, bromo-, and nitro-pentafluorobenzene, and pentafluoropyridine

The reaction of benzoyl peroxide with hexafluorobenzene has been shown to give 2,3,4,5,6-pentafluorobiphenyl and a residue whose relative yields depend mainly on the conditions used for the distillation of the biaryl from the reaction mixtures. This supports the suggestion made previously that the biaryl is formed partly by defluorination of σ-complexes during reaction, and partly by thermal breakdown of dimers of the σ-complexes during the distillation. Analogous phenylation of chloro-, bromo-, and nitro-pentafluorobenzene and pentafluoropyridine gives mixtures of isomeric products. The ratios in which these isomers are formed with chloro- and bromo-pentafluorobenzene and pentafluoropyridine have been measured and are discussed.

Radical reactions in the porphyrin series. The benzoyloxylation of octaethylporphyrin

The reaction of benzoyl peroxide with octaethylporphyrin (1,2,4-trichlorobenzene, 95°, N2) leads to side-chain and meso-substitution products (benzoyloxy-derivatives).

Studies on the reaction of benzoyl peroxide with NN-disubstituted aromatic amines and other related compounds. Part IV. A novel formation of 1,2,3,4-tetrahydroquinoline derivatives

The reaction of benzoyl peroxide with NN-dimethylaniline in cumene or chloroform at ca. 0° in the presence of N-phenylmaleimide gives 1,2,3,4-tetrahydro-1-methylquinoline-N-phenyl-3,4-dicarboximide, formed via the N-methylanilinomethyl radical. This reaction provides a convenient way of differentiating between the PhNMe·ĊH2 radical and the (PhNMe:CH2)+ cation as intermediates. The latter does not react with N-phenylmaleimide, although it reacts with ethyl vinyl ether to give 4-ethoxy-1,2,3,4-tetrahydro-1-methylquinoline. The formation of quinoline derivatives by use of benzoyl peroxide succeeds also with N-methylmaleimide (instead of the N-phenyl compound) and with a number of other aromatic tertiary amines, including N-phenyl- and N-p-tolyl-pyrrolidine; yields of products obtained are of preparative value. Reduction of the products gives 2,3,3a,4,5,9b-hexahydro-5-methyl-2-phenyl-1H-pyrrolo[3,4-c]quinoline, 2,3,3a,3b,4,5,6,11b-octahydro-2-phenyl-1H-dipyrrolo[1,2a,3,4-c]quinoline, and derivatives thereof.

Studies on the Reaction Mechanisms in Heterocyclic Compounds. IV. Ionic Mechanism in the Reaction of Benzoyl Peroxide and Substituted Benzaldehyde (2-Phenyl-3-quinoxalinyl) hydrazone

Studies on the Reaction Mechanisms in Heterocyclic Compounds. IV. Ionic Mechanism in the Reaction of Benzoyl Peroxide and Substituted Benzaldehyde (2-Phenyl-3-quinoxalinyl) hydrazone

Reaction of benzoyl peroxide with furan

The reaction of benzoyl peroxide with furan at temperatures between 35 and 80° was found to proceed without loss of carbon dioxide to give in good yield the cis- and trans-forms of 2,5-dibenzoyloxy-2,5-dihydrofuran.

Aroyl peroxides. Part V. Decomposition of benzoyl peroxide in fluorobenzene

The kinetics and products of the reaction of benzoyl peroxide with fluorobenzene have been studied over a range of initial peroxide concentrations, [P]0. The rate of disappearance of peroxide is governed by simultaneous reactions of order 1·0 and 1·5 corresponding to primary and induced decomposition of the peroxide respectively. A mechanism is proposed which is consistent with the kinetics and products of the reaction and which is analogous to the reaction in benzene rather than to that in chlorobenzene or bromobenzene.

Study of reactions of benzoyl peroxide with amines

Study of reactions of benzoyl peroxide with amines

Studies on the reaction of benzoyl peroxide with NN-dialkyl aromatic amines and other related compounds. Part II. Reactions of some primary and secondary amines

The reaction of benzoyl peroxide with N-methylaniline and N-ethylaniline yields NN′-dimethylhydrazobenzene and NN′-diethylhydrazobenzene, respectively, in addition to previously reported products. The yields of 2-(N-alkylbenzamido) phenols can be increased by carrying out the reaction in benzene in the presence of aqueous sodium hydroxide; this reaction provides a preparative method for the o-hydroxylation of N-alkylanilines. This modification also enables o-benzamidophenols to be obtained from primary aromatic amines.

Studies on the reaction of benzoyl peroxide with NN-dialkyl aromatic amines and other related compounds. Part III. Reactions of some phenolic ethers

Phenolic ethers are much less reactive towards benzoyl peroxide than are NN-dialkylanilines. Benzoyl peroxide in benzene brings about some oxidative dimerisation of o-hydroxyanisoles through the position ortho or para to the hydroxy-group.