Piperazine oxidation

Depending upon the structure of the substrates 49, 52, and 56 hexahydropyrido[l,2-n]-[3,l]benzoxazines 50, 54, 2-aminobenzaldehyde 53, 1-substituted piperidones 51, 55, 57, 3,4,5,6-tetrahydropyridinium salt 58, or their mixture was obtained during the oxidation of 1-(2-hydroxymethyl-, 2-formyl- and 2-acetylphenyl)piperazines (49, 52, 56) with Hg(II)-EDTA complex (Schemes 6-8) (79AP219, 98ZN(B)37, 98ZN(B)1369). 

Phenyl-2-methoxy)ethyl piperazine 3-Phenyl-3-methoxy propylene oxide... 

In a reactor provided with a mechanical stirrer, a reflux refrigerant and a thermometer, there is introduced 393 grams 1-[2-phenyl, 2-methoxy] ethyl piperazine and 22 grams 3-phenyl-3-methoxy propylene oxide in 750 ml of absolute ethanol. 

Phosphorus containing poly(maleimide-amines) were synthesized from N,N -bisdichloromaleimido-3,3 -diphenyl alkylphosphine oxides and aromatic diamines or piperazine [144]. The polymers prepared from piperazine are soluble in DMF, DM AC, DMSO, etc., but have poor thermal stability and flame retardancy. 

Hydroxyethyl)piperazin-l-yl]propyl -8T/-l,2,5-oxadiazolo[3.4-y/]dibcnz[/),/]azepine 1-oxide (19) is the major product (80%) from the reaction of Opipramol (18, see Introduction) with an excess of nitrous acid at 37 rC.218 10- 3-[4-(2-Hydroxyethyl)piperazin-l-yl]propyl -2-nitro-9-acridone (0.1 %). one of numerous minor products formed in this reaction, is a powerful mutagen. 

Oxidation of 11-(piperazin-l-yl)dibenzothiazepinones 1 with hydrogen peroxide gives mixtures of sulfoxides 2 (see also Houben-Weyl, Vol.F.11, p 715) and sulfones 3, whereas periodic acid gives only the sulfoxides.43... 

Piperazine, N-alkylation with benzyl chloride, 42, 19 Piperazine, 1-benzyl-, 42,19 Piperidine, addition to ethylene, 43, 45 as catalyst for Claisen-Schmidt condensation, 41, 40 Piperidine, 1-ethyl-, 43, 45 Piperidine, 1-(2-naphthyl)-, 40,74 Pivalic acid, oxidative coupling to a,a,-a, a -tetramethyladipic add, 40, 92... 

Contact of dicyanofurazan, or its A-oxide (dicyanofuroxan), with hydrazine, mono-or di-methylhydrazine, piperidine, piperazine, diethylamine or their mixtures is instantaneously explosive. 

Tagat, J.R., Steensma, R.W., McCombie, S.W. et al. (2001) Piperazine-based CCR5 antagonists as HIV-1 inhibitors. II. Discovery of 1 - [(2,4-dimethyl-3-pyridinyl)carbonyl]-4- methyl-4- [3 (S)-methyl-4- [ 1 (5)- [4-(trifluoro- methyl)phenyl]ethyl]-l-piperazinyl]-piperidine Nl-oxide (sch-350634), an orally bioavailable, potent CCR5 antagonist. Journal of Medicinal Chemistry, 44 (21), 3343-3346. 

The iV-( -nitrophcnyl)pipcrazinc-2-carbonitrilc 251 (Y = NBOC) was reductively cyclized to the tricyclic /V-oxides 252 (Y = NBOC) either by catalytic hydrogenation, or by electrochemical reduction. Electrochemical reduction gave lower yield. Compounds 251 were prepared by electrochemical cyanation of the iV-(o-nitrophenyl)piperazine 250. The jV-oxides 252 were further hydrogenated to the 2,3,4,4 ,5,6-hexahydro-l//-pyrazino[l,2- ]quinoxaline 253 (Y = NBOC) (Scheme 46) <2001EJ0987>. 

Oxidative cyclization of the alcohol 359 with 2-idoxybenzoic acid (IBX) has been used to obtain the. V.O-hemiacetal 360 as outlined below in Equation (96) <2002TL3699>. Similar strategies have also been employed to access other substituted piperazines <2004CEJ1141, 20040L3881>. 

Phthalic acid Piperazine Platinum Nitric acid, sodium nitrite Oxidizers Acetone, arsenic, hydrazine, lithium, proxosulfuric acid, phosphorus, selenium, tellurium... 

Applying Buchwald s Pd-catalyzed animation methodology, Thomas and coworkers prepared a range of bicyclic piperazine [108]. While Pd-catalyzed animation of 5-bromobenzofuran led to 5-benzofurylpiperizine 136 in 65% yield after deprotection, the corresponding reaction of 7-bromobenzofuran only gave 7-benzofurylpiperizine 137 in 20% yield. They speculated that either steric hindrance of the oxidative addition intermediate or the interaction between the oxygen lone pair and the metal center was responsible for the low yield. The debrominated benzofuran was the major by-product. 

N1 -acylsulfanilamides, 23 508 A21-heterocyclic derivatives, 23 508 Ar -heterocyclic-Ar -acylsulfanilamides, 23 508 A21-heterocyclic sulfanilamides, 23 507—508 2V-(2-aminoethyl)-l,3-propylenediamine physical properties, 5 486t 2V-(2-aminoethyl)-piperazine (AEP), 5 485 N2 oxidation, Birkeland-Eyde process of, 27 291-292, 316. See also Dinitrogen entries Nitrogen entries N3 -P5 phosphoramidates, 27 630-631 Na+, detection in blood, 24 54. See also Sodium entries Nabarro-Herring creep, 5 626 Nacol 18, chain length and linearity, 2 10t Nacreous pigments, 7 836-837 19 412 Nacrite, 6 659... 

Compounds containing a benzodioxole moiety are oxidized by CYPs to generate a carbene that forms a tightly bound complex with the heme iron, easily measurable by UV-Vis spectroscopy. There are numerous examples in the literature paroxetine, MDP alkylamines, MDP benzothiazines, MDP benzothiazolines and MDP piperazines (see Scheme 11.2) [54—60],... 

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