N- 3, 4-piperidine

Piperidine, 3-aryIoxymethyI-4-phenyI-as antidepressant, 1, 169 Piperidine, JV-bromo-photoelectron spectroscopy, 2, 142 Piperidine, cis-4- t-butyl-r- cyclohexyl-1 -phenyl-X-ray analysis, 2, 161 Piperidine, 3-chloro-pyrrolidines from, 4, 147 Piperidine, N-chloro-photoelectron spectroscopy, 2, 142 reactions, 2, 373 trimerization, 3, 510 Piperidine, 4-cycIopentyI-2,6-dioxo-synthesis... 

The pincer complexes 89-90 (Fig. 2.14) catalyse the intramolecular hydroamination/ cyclisation of unactivated alkenes, yielding pyrrolidines and piperidines (n = 1,2, respectively). The reactions can be carried out in benzene or water with high... 

N-VALERIC ACID ISOBUTYL FORMATE N-PROPYL ACETATE ETHYL PROPIONATE METHYL BUTYRATE METHYL ISOBUTYRATE PIPERIDINE N-PENTANE 2-METHYL BUTANE 2 2-DIMETHYL PROPANE... 

The u.v.-visible spectrum of the 4-hydroxy-2,2,6,6-tetramethyl-piperidine-N-oxyl-methyl-cobinamide is very similar to methyl-cobin-amide itself and as a result this technique cannot be used to rigorously identify the spin labeled derivative. The spin labeled compound does show a spectral change with pH between pH 7.0 and pH 2.0 which methyl-cobinamide does not exhibit. Despite the similarities between methyl-cobinamide and nitroxylmethylcobinamide, the circular dichroism spectrum of the two derivatives are quite different. Fig. 23 shows the marked difference in C. D. spectra of 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, methylcobinamide, and a methylcobinamide solution containing an equimolar amount of uncoordinated nitroxide. 

Fig. 23. C. D. Spectra of 4-hydroxy-2,2,6,6-piperidine-N-oxyl-methyl-cobinamide (—) and methyl-cobinamide plus free nitroxide (---—) at 3 x 10 5 M in ethanol...

This approach was followed by Yushmanov for the localization of papaverine in ionic micelles.42 Another interesting application was reported by Chien43 who measured 19F NMR relaxation times of trifluor-omethyl labelled atrazine induced by paramagnetic probes gadolinium ethylenediamine tetraacetic acid and 2,2,6,6-tertramethyl-piperidine-N-oxyl. The results showed that atrazine solubilized by humic micelles occupied a hydrophobic domain accessible only to neutral hydrophobic molecules. 

A more recent publication by Weigand and Pelka has disclosed a polymer-bound Buchwald-Hartwig amination [40], Activated, electron-deficient aryl halides were coupled with conventional PS Rink resin under microwave irradiation. Subsequent acidic cleavage afforded the desired aryl amines in moderate to good yields (Scheme 7.22). Commercially available Fmoc-protected Rink amide resin was suspended in 20% piperidine/N,N-dimethylformamide at room temperature for 30 min to achieve deprotection. After washing and drying, the resin was placed in a silylated microwave vessel and suspended in dimethoxyethane (DME)/tert-butanol... 

In order to test this proposal, several theozymes were constructed.1101 Antibody 26D9 was originally elicited in response to a piperidine-N-oxide hapten (4, Figure 2), in which the polarized N-0 bond was meant to mimic the breaking C-0 bond of the epoxide in the cyclization transition state, and the 6-membered piperidine ring was used to represent the size and shape of the 6-endo transition state Hapten 4 was used as a template to create several... 

The X-ray crystal strudures of antibody 5C8 in complex with piperidine-N-oxide hapten 4 and piperidinium hapten 5 were determined at 2.0 A resolution.1151 In the 5C8 5 complex, two carboxylate residues (AspH95 and AspHlOl) flank the cationic... 

When the decomposition of the zwitterionic intermediate is rate-determining, the effect of the solvent is crucial since it may produce changes in the mechanisms and in the rate-determining step. A recent study of the kinetics of the reactions of 1-chloro-, 1-fluoro- and l-phenoxy-2,4-dinitrobenzene with piperidine, n-butylamine and benzylamine in ethyl acetate and THF indicated that these reactions resemble those in dipolar aprotic solvents when primary amines are the nucleophiles (i.e. that shown in equation 1, with... 

A nitrogen atom at X results in a variable downfield shift of the a carbons, depending in its extent on what else is attached to the nitrogen. In piperidine (45 X = NH) the a carbon signal is shifted by about 20 p.p.m., to ca. 8 47.7, while in N-methylpiperidine (45 X = Me) it appears at 8 56.7. Quaternization at nitrogen produces further effects similar to replacement of NH by N- alkyl, but simple protonation has only a small effect. N-Acylpiperidines show two distinct a carbon atoms, because of restricted rotation about the amide bond. The chemical shift separation is about 6 p.p.m., and the mean shift is close to that of the unsubstituted amine (45 X = NH). The nitroso compound (45 X = N—NO) is similar, but the shift separation of the two a carbons is somewhat greater (ca. 12 p.p.m.). The j8 and y carbon atoms of piperidines, N- acylpiperidines and piperidinium salts are all upheld of the cyclohexane resonance, by 0-7 p.p.m. 

Anders als bei der katalytischen Hydrierung wird bei der Reduktion von N-substituierten Carbamidsiiure-alkylestern mit Lithium-alanat die N-Alkoxycarbonyl-Gruppe nicht ab-gespalten, sondern zur Methyl-Gruppe reduziert. So erhalt man z.B. bei der Reduktion von ( + )-l-Methoxycarbonyl-2-propyl-piperidin mit Lithium-alanat in siedendem Ether ( + )-l-Methyl-2-propyl-piperidin [( + )-N-Methyl-coniin 64%]3. 

Free Radical Initiator Modifiers a. Piperidine N-oxide derivatives... 

Sedum sarmentosum Bunge. Chui Pen Chao or Jing Tian (Stringy stonecrop) (whole plant) Sarmentoslin, dihydro-N-methyl-isopelletierine, N-methyl-2-((3-OH-propyl) piperidine, N-methyl-isopelletierine, dl-methylisopelletierine, dihydroisopelletierine.33-48-50 Antipyretic, detoxicant, diuretic, treat hepatitis. 

Dibutylamine, piperidine, N-ethylcyclohexylamine, N-ethyldicyclohexylamine, and the ketones were reagent grade chemicals. The 5% palladium on carbon, 5% platinum on carbon, sulfided 5% platinum on carbon and sulfided 5% rhodium on carbon catalysts were obtained from Engelhard Industries. The 20% molybdenum sulfide on alumina (Girdler T-318) was obtained from the Chemetron Corp. Palladium chloride was obtained from Matheson, Coleman and Bell. Ruthenium trichloride was obtained from Ventron. 

A -Piperideine — see Pyridine, 2,3,4,5-tetrahydro-A2-Piperideine — see Pyridine, 1,2,3,4-tetrahydro-A3-Piperideine — see Pyridine, 1,2,3,6-tetrahydro-Piperideines — see Pyridines, tetrahydro-Piperidine, 1-acryloyl-polymers, 1, 284 Piperidine, N-acyl-... 

Piperidine, l-(2-hydroxythiobenzoyl)-neutron diffraction, 2, 116 Piperidine, 4-hydroxy-2,2,6-trimethyl-as local anaesthetic, 1, 179 Piperidine, N-methoxycarbonyl-electrolytic oxidation, 2, 374 Piperidine, 2-methyl-synthesis, 2, 524 Piperidine, 3-methyl-mass spectrometry, 2, 130 Piperidine, C-methyl-NMR, 2, 160 Piperidine, N-methyl-l3C chemical shifts, 2, 15 catalyst... 

Thus, 395 gives via pyrolysis 2,4,6-tris(trimethylsiloxy)-3-pyridinecarbonitrile (399) and subsequent hydrolysis 2,4,6-trioxo-3-piperidine carbonitrile (400) whereas direct hydrolysis of395 leads to 2,4,6-trioxopiperidinecarboxamide (39 7). Analogously, 396 affords by direct hydrolysis 1-methyl-2,4,6-trioxo-3-piperidine[N-methylcar-boxamide] (398). 

Brouwer and Krijnen (95JOC32), by ab initio and semi-empirical quantum chemical calculations of piperidine, N-methylpiperidine and a number of derivatives incorporating 7r-electron acceptors at the 4-position... 

Based on these assumptions of the mechanism of action, Ferrutti and Marchisio (22) have examined several N-oxides like poly(3-vinylpyridin-l-oxide), poly(N-allyl-piperidine-N-oxide), poly(p-dimethyl-aminostyrene-N-oxide) and other analogous substances. They have been able to demonstrate that these substances show the same activity. 

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