Oxidation Of Tertiary Amines Research Articles

Studies in tertiary amine oxides part II—carbon‐13 nuclear magnetic resonance spectra of selected acetylenic amines, their N‐oxides and the Meisenheimer rearrangement products

AbstractCarbon‐13 NMR chemical shifts and 1J(CH), 2J(CH) and 3J(CH) coupling constants of selected saturated nitrogen heterocyclic molecules containing the acetylenic moiety have been determined. These NMR parameters have also been determined for the corresponding N‐oxides and the Meisenheimer rearrangement products, the O‐allenylhydroxylamines. The effect of the N‐oxidation on the chemical shifts of the ring and the acetylenic carbon atoms is discussed.

Studies on tertiary amine oxides. LXVIII. . Reactions of aromatic N‐oxides with 2‐substituted 2‐oxazolin‐5‐ones in the presence of acetic anhydride

AbstractQuinoline l‐oxides 1a‐f readily react with 2‐phenyl‐ and 2‐methyl‐2‐oxazolin‐5‐ones, 2a and 2b, in the presence of acetic anhydride to afford 2‐substituted 4‐(2‐quinolyl)‐2‐oxazolin‐5‐ones 3a‐h in good yields. Hydrolysis of 3a‐f with 10% hydrochloric acid under refluxing conditions gives the corresponding 2‐amino‐methylquinoline dihydrochlorides 5a‐e or monohydrochloride 5f also in good yields. Similar results are obtained from reactions of isoquinoline 2‐oxide 9 with 2a,b under the same conditions.

TRIPHASE CATALYSIS OF POLYMER-BOUND AMINE OXIDE IN CYANIDE DISPLACEMENT ON 1-BROMOOCTANE

Abstract Cross-linked polystyrene supported tertiary amines and amine oxides are found to be a very efficient catalyst for a nucleophilic substitution reaction. The amine oxide resin (MPE-5-AO) was one of the most effective and economical catalysts and can be used several times without the loss of the catalytic activity.

Studies on tertiary amine oxides. LXVII . Reactions of aromatic N‐oxides with 3‐arylrhodanines in the presence of acetic anhydride

AbstractQuinoline 1‐oxides 1 readily react with 3‐arylrhodanines 2 in the presence of acetic anhydride to afford 3‐aryl‐5‐(2‐quinolyl)rhodanines 3 in high yields. These products resist hydrolysis under both alkaline and acidic conditions, but is oxidized to quinaldinic acid 1‐oxide 4 with 30% hydrogen peroxide in hot acetic acid. Besides isoquinoline 2‐oxide 5, pyridine 1‐oxide 7a also reacts in the same way to give 3‐aryl‐5‐(2‐pyridyl)rhodanines 8, although the reactivity of γ‐picoline 1‐oxide 7b is considerably lower. Contrary to 3, 3‐phenyl‐5‐(2‐pyridyl)rhodanine 8a is successfully hydrolyzed with boiling 48% hydrobromic acid to 2‐pyridinemethanethiol 10 in 57% yield.

Studies on tertiary amine oxides. LXVI. Reactions of quinoline 1-oxide derivatives with tosyl chloride in the presence of triethylamine.

Reactions of N-oxides of lepidine (1a) and 4-methyl- (1b), 4-chloro- (1c) and 6-methoxyquinoline (1d) with tosyl chloride (1 eq) and triethylamine (ca. 10 eq) in a mixture of chloroform and water at room temperature gave the corresponding di (2-quinolyl) ethers (3a-d) and N-(2-quinolyl)-2-quinolones (4a-d). The efficiency of this type of reaction depends upon the nature and position of the substituents. Whereas the reaction of 1c with carbostyril under the same conditions gave small amounts of 4-chloro-2-tosyloxyquinoline (2c) and N-(4-chloro-2-quinolyl)-4-chloro-2-quinolone (4c), that of 1d afforded 6-methoxy-2-quinolyl 2'-quinolyl ether (15) and N-(6-methoxy-2-quinolyl)-2-quinolone (16) in 47 and 29% yields, respectively.

Studies on tertiary amine oxides. LXIX. Reactions of 2-chloromethylquinoline derivatives with 2-nitropropane.

Reactions of 2-chloromethylquinoline (1), its N-oxide (2) and their nitro derivatives with the sodium salt of 2-nitopropane were investigated. O-Alkylation occurred with 1 and 2, giving 2-quinolinecarboxyaldehyde (5 : 11%) and its N-oxide (6 : 10%). The reaction of 2-chloromethyl-5-nitroquinoline (3b) gave both the O-alkylation product, 5-nitro-2-quinolinecarboxyaldehyde (7 : 21%), and the C-alkylation products, 2-(2-methyl-2-nitropropyl)-5-nitroquinoline (8b : 24%) and 2-(2-methyl-1-propenyl)-5-nitroquinoline (9b : trace). In the reactions of the 6-nitro (3c) and 8-nitro (3d) derivatives of 1, the 2-(2-methyl-2-nitropropyl) quinolines (8c : 86% and 8d : 63%) were predominantly formed. In contrast, the reactions of the 4-nitro (4a), 5-nitro (4b) and 6-nitro (4c) derivatives of 2 produced the corresponding 2-(2-methyl-1-propenyl) quinoline N-oxides (11a : 53%, 11b : 20% and 11c : 66%) as main products, accompanied by small amounts of the 2-(2-methyl-2-nitropropyl) compounds (10a : 20% and 10b : 17%).

Tertiary amine oxides as phase transfer catalysts for substitution and dichlorocyclopropanation reactions

Tertiary amine oxides catalyze a variety of phase transfer reactions, primarily by in situ deoxygenation to form the tertiary amine or derived catalyst.

Formation of superoxide radical anion in the horseradish peroxidase-catalysed oxidation of three aromatic tertiary amines with hydrogen peroxide

The horseradish peroxidase-catalysed oxidation of aromatic tertiary amines with hydrogen peroxide to give a secondary amine and an aldehyde occurs through the co-occurrence of the usual reaction with H2O2 and a free radical chain reaction which depends upon oxygen concentration. The intervention of superoxide radical anion is demonstrated by the reduction of cytochrome CIII and the dismutation catalysed by superoxide dismutase.

Electronic, steric and lipophilicity requirements in the oxidation of dialkylarylamines by horseradish peroxidase

Horseradish peroxidase (HRP)catalyzes the oxidation of a wide variety of organic compounds by hydrogen peroxide. The mechanism has been established and described by the following scheme: HRP + H 2O 2 ⇄ HRP-H 2O 2 → E 1 ▪ where E 1 and E 2 are oxidized forms of the enzyme at respectively two and one level of oxidation. In previous work we have shown that HRP catalyzes the oxidation of aromatic tertiary amines with hydrogen peroxide yielding a secondary amine and an aldehyde according the reaction ▪ In this reaction oxygen is consumed. From stoicheiometricalexperiments the following mechanism has been proposed: Since the hydrogen peroxide-peroxidase system is often regarded as a simple model for more complex biological oxidative systems, we have studied the structure requirements in the oxidation of some dialkylarylamines with this system. A kinetic investigation was performed on a series of fifteen N,N-dimethyl (1-8) and diethylanilines (9-15). Within the experimental range of concentrations initial rates were linearly dependent on initial substrate concentrations. The apparent first order constants were calculated. Diethylanilines react on the average 2.6 times faster than dimethylderivatives. This parallelism reduces the possibility of dealing with random points distribution. In spite of this, statistical treatment of data by single or multiple regression does not show any linear expression of reactivity as a function of Hammett's σ, Hansch's π lipophilicity and MR steric parameters. Different rate determining steps may be supposed within the substrates series. However some empirical observations can be made. Reactivity is lowered by hydrophobic and electron withdrawing substituents and exalted by hydrophilic and electron donor substituents. Bulkiness of substrate has no peculiar importance. These results are in analogy with other data ▪ (1) X = 4-F (9) X = 4-F (2) 3-Cl (10) 3-Cl (3) 4-Cl (11) 4-Cl (4) 3-Me (12) 3-Me (5) 4-NHCOCH 3 (13) 4-NHCOCH 3 (6) 4- isoC 3H 7 (14) 4- isoC 3H 7 (7) 4-CN (15) 3-OCH 3 (8) 3-NO 2 obtained for the.oxidation of dialkylarylamines with rat liver microsomal P-450 dependent detoxifying system.

The Meisenheimer rearrangement in heterocyclic synthesis. III. Derivatives of the 1H-[1,2]oxazepino[6,5-b]indole, thieno[2,3-e][1,2]oxazepine and [l]benzothieno[3,2-e][1,2]oxazepine ring systems

The new heterocyclic derivatives 3-methyl-1-phenyl-3,4,5,10-tetrahydro- 1H-[1,2]oxazepino[6,5-b]-indole (5c), 6-methyl-4-phenyl-4,6,7,8- tetrahydrothieno[2,3-e][1,2]oxazepine (6f), and 3-methyl-1-phenyl- 1,3,4,5-tetrahydro[1]benzothieno[3,2-e][1,2]oxazepine (7c) were prepared in good yield by thermal Meisenheimer rearrangement of the corresponding tertiary amine N-oxide precursors. No such rearrangement occurred on heating the N-oxides of the fused bicyclic systems 2,3,11,12-tetramethoxy-5,8,9,13b-tetrahydro-6H-dibenzo[a,h]quinolizine (3) and 8,9-dimethoxy-1,2,3,5,6,10b-hexahydropyrrolo[2,1-a]isoquinoline (4). The reduction of (5c), (6f) and (7c) with zinc in acetic acid is also described.

Studies of tertiary amine oxides. LXV. Reaction of quinoline 1-oxide with tosyl chloride in the presence of triethylamine.

Chinolin-N-oxid (I) reagiert mit Tosylchlorid (II) in Gegenwart von Triethylamin hauptsachlich zum Dichinolylether (IV) und dem Chinolyllactam (V) neben dem Tosylat (III) und dem Lactam (VI).

Purification and Some Properties of Inducible Tertiary Amine N-Oxide Reductase from Escherichia coli 1

Formation of amine N-oxide reductase in E. coli was repressed by tungstate but not when molybdate was present. Four forms of this reductase with different electrophoretic mobilities on polyacrylamide gel were found by active staining using the supernatant obtained by the centrifugation at 17,000 x g of the extract from cells grown in the presence of trimethylamine AT-oxide; one of them was constitutive and the other three, including the most active, were inducible. The reductase found in the precipitate obtained by centrifugation at 100,000 X g was solubilized by treatment with Emulgen 810 and showed two forms, one of which corresponded to the most active form found in the supernatant. The reductase was purified from the supernatant to an almost homogeneous state by ammonium sulfate precipitation and DEAE-cellulose, Sephadex G-200, double DEAE-Sephadex A-25, and hydroxyapatite chro-matographies. Specific activity was increased about 100 fold and recovery was 1%. The enzyme corresponded to the most active form. The purified enzyme reduced various N-oxides of purine and pyridine derivatives as well as trimethylamine iV-oxide, hydroxylamine, chlorate, and bromate. The optimal pH's for trimethylamine JV-oxide, adenosine N-oxide, and hydroxylamine were 5.3, 6.0, and 6.0, and Km values 1.5 itim, 0.36 mM, and 53 mM, respectively. FMN and FAD, but not cytochrome c, served as electron donors beside benzyl and methyl viologen, though the reaction rates were about one tenth. The enzyme was activated by ferric ion, and severely inhibited by cupric ion. The spectrum showed a peak at 280-nm and a shoulder at 385 nm. Molecular weight was estimated to be 220,000 by Sephadex G-200 gel filtration. Isoelectric point was pH 5.2. Iron content was 1.8mol/mol. The enzyme was found to consist of at least two sorts of subunits, the molecular weights of which were found to be 60,000 and 80,000 by SDS-polyacrylamide gel electrophoresis. The amino acid composition is also presented.

Additions and Corrections - 4a-Hydroperoxyflavin N-Oxidation of Tertiary Amines

Additions and Corrections - 4a-Hydroperoxyflavin N-Oxidation of Tertiary Amines

Oxidation of tertiary amines with N‐chloronylon 66

AbstractOxidation of tertiary amines with N‐chloronylon 66 (NCN) was investigated in several organic solvents. NCN was found to oxidize N,N‐dimethylaniline (DMA) at room temperature to give N‐methylaniline with 15–50% yield, depending on the solvents used. Oxidation of N,N‐dimethylbenzylamine (DMBA) gave benzaldehyde with 15–30% yield and a small amount of N‐methylbenzylamine. A mechanism was discussed. For comparison, N‐chlorosuccinimide, a low molecular N‐chloro‐compound, was also used for oxidation of DMA and DMBA.

Reactions concerned in tertiary amine N-oxides. XII. The synthesis of asymmetric compounds containing the ferroin or cuproin group (author's transl)

Reactions concerned in tertiary amine N-oxides. XII. The synthesis of asymmetric compounds containing the ferroin or cuproin group (author's transl)

Reduction of benzydamine N-oxide by rat liver xanthine oxidase.

Evidence is presented that a purified xanthine oxidase preparation, like milk xanthine oxidase, is responsible for the xanthine-dependent reduction of benzydamine N-oxide. Rat liver preparations contain enzymes which catalyze the anaerobic reduction of benzydamine N-oxide by either reduced nicotinamide adenine dinucleotide (phosphate) NAD (P) H or xanthine. In crude enzyme preparations, the enzymatic reduction seems to involve xanthine oxidase and/or cytochrome P-450 because allopurinol, an inhibitor of xanthine oxidase, and n-octylamine, an inhibitor of aliphatic tertiary amine N-oxide reductase (cytochrome P-450) block the reduction of benzydamine N-oxide in crude enzyme preparations of rat liver. Moreover, the enzymatic system exhibited dual pH optima of 7.4 and 9.0 for reductions dependent on NADPH and xanthine, respectively. An enzyme preparation which did not contain cytochrome P-450 was isolated from rat liver and purified 186-fold in terms of xanthine oxidase activity. Xanthine oxidase activity and xanthine-dependent benzydamine N-oxide reduction activity were copurified in parallel.

Evidence for ipso attack in the peroxodisulfate oxidation of tertiary aromatic amines

Evidence for ipso attack in the peroxodisulfate oxidation of tertiary aromatic amines

Horseradish peroxidase-catalysed oxidation of aromatic tertiary amines with hydrogen peroxide

The horseradish peroxidase-catalysed oxidation of aromatic tertiary amines with hydrogen peroxide leads to a secondary amine and an aldehyde. With alkylmethylanilines demethylation is preferred to dealkylation. Evidence is given for the coexistence of the usual peroxidation reaction and a free radical chain reaction which depends upon oxygen concentration.

Reactions concerned in tertiary amine N-oxides. X. Reactions of diazines with pyridine N-oxide (author's transl)

Reactions concerned in tertiary amine N-oxides. X. Reactions of diazines with pyridine N-oxide (author's transl)

Reactions concerned in tertiary amine N-oxide. XI. Oxidation of lactic acid derivatives with pyridine N-oxide using ferric or ferrous ion catalyst (author's transl)

Reactions concerned in tertiary amine N-oxide. XI. Oxidation of lactic acid derivatives with pyridine N-oxide using ferric or ferrous ion catalyst (author's transl)