2403-88-5Relevant articles and documents
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Chen,Le Fevre
, p. 3467,3470 (1965)
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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.
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.
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.
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.