Benzylamine, oxidation

The comparison of the bands observed after benzonitrile and benzylamine transformation over vanadia-titania allows us to suggest that benzamide can also be obtained by oxidation of benzylamine. Moreover, the growth of the absorption near 1640 cm and the appearance of bands at 1330 and 1240 cm during benzylamine oxidation suggests that benzaldehyde is also formed. A likely assignment for the band at 1670 cm is to the stretching of a C=N double bond (75), so being likely indicative of the formation of benzaldimine. 

Topaquinone (TPQ), the oxidized form of 2,4,5-trihydroxyphenylalanine (TOPA), is the cofactor of copper-containing amine oxidases. The following model compounds have been prepared in order to understand the catalytic function of TPQ the jV-pivaloyl derivative of 6-hydroxydopamine in aqueous acetonitrile [38] topaquinone hydantoin and a series of 2-hydroxy-5-alkyl-l,4-benzoquinones in anhydrous acetonitrile (o- as well as />-quinones) [39] 2-hydroxy-5-methy 1-1,4-benzoquinone in aqueous system [40] and 2,5-dihydroxy-1,4-benzoquinone [41]. Reaction of model compounds with 3-pyrrolines revealed why copper-quinopro-tein amine oxidases cannot oxidize a secondary N [42], The studies clearly showed that certain model compounds do not require the presence of Cu for benzylamine oxidation whereas TPQ does [38,40] the aminotransferase mechanism proceeds via the -quinone form [39] the 470 nm band can be ascribed to a 71-71 transition of TPQ in />-quinonic form with the C-4 hydroxyl ionized but hydrogen bonded to some residue [40] hydrazines attack at the C-5 carbonyl, forming an adduct in the azo form [41], Electrochemical characterization has been carried out for free TPQ [43],... 

Treatment of virosecurinine 108 with monoperphthalic acid gave two nonbasic isomeric products, 123 and 124, in a 1 5.5 ratio. The oxidative reaction may be envisaged to proceed via the A-oxide intermediate 122 which suffers rearrangement analogous to known transformations of A-allyl- and A-benzylamine oxides to 0-allyl and... 

Oxygenation takes place with peracids. The cyclopalladated benzylamine complex 466 is converted into the salicylaldamine complex 504 by the treatment with MCPBA[456] or /-BuO H[457]. Similarly, azobenzene is oxidized with MCPBA at the ortho position[458]. 

The chelated complex of the benzylamine derivative 505 underwent a remarkable oxidative transformation by treatment with thallium trifluoroace-tate to give narwedine (506) in one step by biomimetic oxidation[459]. 

I, 4- and 3,4-Dihydroquinazolines are tautomeric but any attempts to prepare the former w ithout a 1-substituent have led to the latter. The greater stability to proto tropic change of 1,2-dihydronaphthalene over 1,4-dihydronaphthalene is also found in 3,4-dihydroquinazoline. Earlier claims to the preparation of l,4-dihydroquinazolines ° were erroneous and based on incomplete experimental data. The first 1,4-dihydroquinazoline was prepared as recently as 1961. 1-Methyl and l-benzyl-l,4-dihydroquinazolines were obtained from o-methylamino-and o-benzylamino-benzylamines (42) by formylation and ring closure. Attempts to remove the benzyl group gave 3,4-dihydroquinazoline. These 1,4-dihydro compounds are susceptible to oxidation, and attempts made to prepare 1,2-dimethyl-1,4-dihydroquinazoline from o-... 

N-Benzylidene-benzylamine N-oxide Benzenemethanamine, N-(phenylmethylene)-, N-oxide (3376-26-9)... 

Ben2yl azide 1855 and N-benzyloxycarbonylbenzylamine 1859 are both transformed by the cheap polymethylhydrosiloxane (PMHS) 1856, in the presence of (B0C)20 and Pd/C, into 92-94% N-BOC-benzylamine 1857 and the polymer 1858 [81]. (Scheme 12.22). Aromatic and aliphatic amine oxides are readily reduced by 1856/Pd/C into their corresponding amines. Thus, e.g., pyridine-N-oxide 860 and quinohne-N-oxide 877 give pyridine and quinohne in 90 and 92% yield, respectively. Analogously, benzyldimethylamine-N-oxide is converted in 88% yield into free benzyldimethylamine [82]. 

Medvedev AE, Veselovsky AV, Shvedov VI, Tikhonova OV, Moskvitina TA, Fedotova OA, et al. Inhibition of monoamine oxidase by pirlindole analogues 3D-QSAR and CoMFA analysis. / Chem Inf Comput Sci 1998 38 1137-44. Miller JR, Edmondson DE. Structure-activity relationships in the oxidation of para-substituted benzylamine analogues by recombinant human liver monoamine oxidase A. Biochemistry 1999 38 13670-83. 

A comprehensive account of the oxidation of benzylamine by both neutral and alkaline permanganate has been published recently . The neutral amine is the active reductant at all pH values and at pH 9.9 good second-order kinetics were obtained. Under these conditions the stoichiometry is... 

In the same paper the authors list the responses of a number of amines and amides towards permanganate and record the effect of freezing the medium upon the oxidation of benzylamine. 

Madsen and co-workers have reported an important extension to the amine alkylation chemistry, in which oxidation takes place to give the amide product [13]. A ruthenium NHC complex is formed in situ by the reaction of [RuCl Ccod)] with a phosphine and an imidazolium salt in the presence of base. Rather than returning the borrowed hydrogen, the catalyst expels two equivalents of H. For example, alcohol 31 and benzylamine 27 undergo an oxidative coupling to give amide 32 in good isolated yield (Scheme 11.7). 

Rearangement of furoxans leads to the formation of new heterocyclic systems derivatives of triazoles, diazoles, isoxazoles, and pyrimidinones. For example, on the basis of the experimental results using labeled compound 52-15N , the formation of 8-phenyltheophylline 53, the 1,3-dimethylalloxazines (54 n = 0, 1), and l,3,7,9-tetramethyl-l//,9//-pyrimido[5,4-g]-pteridine-2,4,6,8-tetraone 55 in the thermal reaction of the iV-oxide 52 with benzylamine, aniline, or piperidine and the generation of NO or NO-related species in the reaction with iV-acetylcysteamine were reasonably explained by... 

A new pyrrole ring synthesis developed by Arcadi involves the addition of ammonia or benzylamine to 4-pentynones, the latter of which are conveniently prepared via a palladium oxidative coupling sequence as shown below for the synthesis of 40 [39,40]. 

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