2403-88-5Relevant articles and documents
ELECTROCHEMICAL SYNTHESIS OF 2,2,6,6,-TETRAMETHYLPIPERIDINE
Kagan E. Sh.,Avrutskaya, I. A.,Kondrashov, S. V.,Novikov, V. T.,Fioshin, M. Ya.,Smirnov, V. A.
, p. 288 - 289 (1984)
A preparative method for the production of 2,2,6,6-tetramethylpiperidine based on the electrochemical reduction of 4-oxo-2,2,6,6-tetramethylpiperidine in 30percent sulfuric acid on cadmium or lead electrodes was developed.
Reductive amination of triacetoneamine with n-butylamine over Cu-Cr-La/γ-Al2O3
Sun, Meng,Du, Xiaobao,Wang, Huabang,Wu, Zhiwei,Li, Yang,Chen, Ligong
, p. 1703 - 1708 (2011)
A series of Cu-based catalysts were prepared and examined for the reductive amination of triacetoneamine with n-butylamine, thereinto, Cu-Cr-La/γ- Al2O3 showed excellent results. The catalysts were studied by XRD, XPS, H2-TPR and NH3-TPD. It was found that doped Cr remarkably enhanced the activity of Cu/γ-Al2O3 due to better dispersion of Cu0, which is believed to be the active site for the reductive amination. Additionally, it was obvious that introduction of La to Cu-Cr/γ-Al2O3 led to a higher selectivity and longer lifetime. The reaction parameters were optimized and N-butyl-2,2,6,6-tetramethyl-4-piperidinamine was obtained in a yield of 94%. Graphical Abstract: The addition of Cr does not impact obviously on the total acidity of Cu20/γ-Al2O3. However, the La addition to Cu20Cr5/γ-Al2O3 not only decreases the total acidity but also reduces the strength of acid sites. The introduction of La was found to result in a higher selectivity and longer lifetime. The conversion of TAA and selectivity of TEMPBA remained around 99.7 and 94.5% in 120 h.[Figure not available: see fulltext.][Figure not available: see fulltext.]
Crowded piperidines with intramolecularly hydrogen-bonded nitrogen: Synthesis and conformation study
Belostotskii, Anatoly M.,Gottlieb, Hugo E.,Aped, Pinchas
, p. 3016 - 3026 (2002)
2,2,6,6-Tetramethyl substituted piperidines with a β-branched N-alkyl substituent were synthesized by the photoreaction of N-Me precursors with ketones. The main conformation features of these sterically-hindered amines (established by NMR and IR spectroscopy) are a ring in the chair form, an eclipsed conformation for the N-substituent and an intramolecular OH···N bond. High barriers for the geminal substituent topomerization were measured for these piperidines at different temperatures by means of line-shape analysis of the temperature-dependent 13C and 1H NMR spectra. An MM3-derived conformation scheme indicated that, for one of the studied analogues, the rotation of the N-substituent determines a slow topomerization rate. A new mechanism of nitrogen inversion - a concerted hydrogen-bond dissociation/nitrogen inversion process - is considered for hydrogen-bonded amines.
A continuous process for the production of 2,2,6,6-tetramethylpiperidin-4- ol catalyzed by Cu-Cr/γ-Al2O3
Fan, Xiaopeng,Liu, Shuai,Yan, Xilong,Du, Xiaobao,Chen, Ligong
, p. 960 - 963 (2010)
A continuous processwas established for the production of 2,2,6,6-tetramethylpiperidin-4-ol over Cu-Cr/α-Al2O3 in a fixed-bed reactor. The catalystwas characterized by X-ray diffraction, X-ray photoelectron spectroscopy and temperature-programmed reduction. Cu was believed to be the active site for the hydrogenation, and the doped chromium was supposed to exert a positive impact on the dispersion of active species. The catalyst and parameters of hydrogenation were optimized. Thus, 2,2,6,6-tetramethylpiperidin-4-ol was obtained in the yield of 90% from 2,2,6,6-tetramethylpiperidin-4-one (purity, 95%) under the optimum reaction conditions.
Chemistry and anti-herpes simplex virus type 1 evaluation of 4-substituted-1H-1,2,3-triazole-nitroxyl-linked hybrids
Cunha, Anna C.,Ferreira, Vitor F.,Vaz, Maria G. F.,Cassaro, Rafael A. All?o,Resende, Jackson A. L. C.,Sacramento, Carolina Q.,Costa, Jéssica,Abrantes, Juliana L.,Souza, Thiago Moreno L.,Jord?o, Alessandro K.
, p. 2035 - 2043 (2020/05/25)
Abstract: HSV disease is distributed worldwide. Anti-herpesvirus drugs are a problem in clinical settings, particularly in immunocompromised individuals undergoing herpes simplex virus type 1 infection. In this work, 4-substituted-1,2,3-1H-1,2,3-triazole linked nitroxyl radical derived from TEMPOL were synthesized, and their ability to inhibit the in vitro replication of HSV-1 was evaluated. The nitroxide derivatives were characterized by infrared spectroscopy and elemental analysis, and three of them had their crystal structures determined by single-crystal X-ray diffraction. Four hybrid molecules showed important anti-HSV-1 activity with IC50 values ranged from 0.80 to 1.32?μM. In particular, one of the nitroxide derivatives was more active than Acyclovir (IC50 = 0.99?μM). All compounds tested were more selective inhibitors than the reference antiviral drug. Among them, two compounds were 4.5 (IC50 0.80?μM; selectivity index CC50/IC50 3886) and 7.7 times (IC50 1.10?μM; selectivity index CC50/IC50 6698) more selective than acyclovir (IC50 0.99?μM; selectivity index CC50/IC50: 869). These nitroxide derivatives may be elected as leading compounds due to their antiherpetic activities and good selectivity. Graphic abstract: [Figure not available: see fulltext.]
General methodology for the chemoselective N-alkylation of (2,2,6,6)-tetramethylpiperidin-4-ol: Contribution of microwave irradiation
Membrat, Romain,Vasseur, Alexandre,Giordano, Laurent,Martinez, Alexandre,Nuel, Didier
supporting information, p. 240 - 243 (2019/01/04)
A convenient method to access a broad variety of N-alkyl-(2,2,6,6)-tetramethylpiperidin-4-ol compounds is reported. The thermal treatment of a mixture of (2,2,6,6)-tetramethylpiperidin-4-ol and allyl or benzyl bromide derivatives gave the corresponding N–alkylated compounds in good yields while leaving the hydroxyl functional group intact. Whereas 40 h were needed to reach complete conversion, microwave irradiation allowed the reaction time to be reduced (20 min) and improved the yields in most cases.
Phosphinous Acid Platinum Complex as Robust Catalyst for Oxidation: Comparison with Palladium and Mechanistic Investigations
Membrat, Romain,Vasseur, Alexandre,Martinez, Alexandre,Giordano, Laurent,Nuel, Didier
supporting information, p. 5427 - 5434 (2018/10/20)
Secondary phosphine oxides proved to be effective preligands to stabilise a hydroxy-platinum based catalyst that allows the aerobic/anaerobic oxidation of challenging substrates. Kinetic comparisons showed that this system is more efficient and stable than previously reported similar palladium-based catalysts. A neutral platinum dimer bearing bridging hydroxy ligands has been isolated and fully characterised by X-ray diffraction and its involvement in the mechanism has been evidenced by mechanistic studies.
2′-Alkynylnucleotides: A Sequence- and Spin Label-Flexible Strategy for EPR Spectroscopy in DNA
Haugland, Marius M.,El-Sagheer, Afaf H.,Porter, Rachel J.,Pe?a, Javier,Brown, Tom,Anderson, Edward A.,Lovett, Janet E.
supporting information, p. 9069 - 9072 (2016/08/05)
Electron paramagnetic resonance (EPR) spectroscopy is a powerful method to elucidate molecular structure through the measurement of distances between conformationally well-defined spin labels. Here we report a sequence-flexible approach to the synthesis of double spin-labeled DNA duplexes, where 2′-alkynylnucleosides are incorporated at terminal and internal positions on complementary strands. Post-DNA synthesis copper-catalyzed azide-alkyne cycloaddition (CuAAC) reactions with a variety of spin labels enable the use of double electron-electron resonance experiments to measure a number of distances on the duplex, affording a high level of detailed structural information.
A 2, 2, 6, 6-tetramethyl-4-piperidinol preparation method
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Paragraph 0021-0022; 0024; 0026; 0028; 0030, (2017/09/12)
The invention discloses a preparation method of 2,2,6,6-tetramethyl-4-piperidinol. The preparation method comprises the following steps: A, adding acetone, an organic solvent and a catalyst into a high-pressure reactor, slowly introducing ammonia into the reactor at 20-80 DEG C, and reacting for 1-5 hours; B, slowing introducing hydrogen into the reactor at 20-180 DEG C and reacting for 1-5 hours; and C, cooling the reaction liquid to room temperature, standing and dissolving out 2,2,6,6-tetramethyl-4-piperidinol as white crystal. The organic solvent is one of toluene, dimethylbenzene, mesitylene, petroleum ether, dimethoxyethane or aliphatic alcohol. The catalyst is a metal chloride loaded by activated carbon. In the invention, the technology of one-pot cascade catalytic reaction is adopted, the operation is simple, the product yield is high, and little three-waste is produced, therefore, the method is a economic, practical and pollution-free synthetic technology.
A monolith immobilised iridium Cp catalyst for hydrogen transfer reactions under flow conditions
Rojo, Maria Victoria,Guetzoyan, Lucie,Baxendale, Ian. R.
, p. 1768 - 1777 (2015/02/19)
An immobilised iridium hydrogen transfer catalyst has been developed for use in flow based processing by incorporation of a ligand into a porous polymeric monolithic flow reactor. The monolithic construct has been used for several redox reductions demonstrating excellent recyclability, good turnover numbers and high chemical stability giving negligible metal leaching over extended periods of use.
