Jambulingam, Marimuthukandar; Nanjappan, Palaniappan; Arulvani, Palaniappan, Journal of the Chemical Society. Perkin transactions II, 1986, p. 957 - 960
The rates of oximeformation of 41 heterocyclic ketones have been measured at 5 °C in aqueous alcoholic solution buffered at pH 6.85. The data indicate an overall second-order reaction, first order each in ketone and hydroxylamine. In all cases investigated the reaction appears to be irreversible under the experimental conditions employed. Increased steric retardation is observed as steric crowding
Kinetics of the oxidation of six pairs of epimeric piperidin-4-ols by cerium(IV) in the presence of sulphuric acid in an aqueous acetic acid medium at 60°C have been investigated. The corresponding α-deuteriated piperidin-4-ols have been prepared and their oxidation rates measured. The oxidation is first-order in both oxidant and substrate at constant acid concentration. Mechanisms involving free-radical
在60°C的乙酸水溶液中,在硫酸存在下,铈(IV)氧化了六对对映体哌啶-4-醇的氧化动力学。已经制备了相应的α-氘代哌啶-4-醇,并测量了它们的氧化速率。在恒定的酸浓度下,氧化剂和底物的氧化都是一级反应。提出了涉及自由基中间体的机理。在t -2,t -6-diphenyl- c -3-isopropyl- N -methyl-piperdin- r -4-ol(4)的情况下观察到的动力学同位素效应(k H / k D= 6.26)表明速率确定步骤涉及甲醇碳的C–H(或C–D)键。为了限制t -2,t -6的氧化反应中没有动力学同位素效应(k H / k D = 1.00),提出了一种在速率限制步骤中涉及OH键参与的替代机制。-二苯基-c -3,c -5,N-三甲基哌啶-r -4-ol(5)和c -2,c -6-二苯基-t -3,t -5,N-三甲基哌啶-r-4-醇(14)。这两种机理可能同
The Preparation of Some Piperidine Derivatives by the Mannich Reaction
作者:C. R. Noller、V. Baliah
DOI:10.1021/ja01191a092
日期:1948.11
A piperidinium triflate catalyzed Biginelli reaction
A piperidinium triflate, 1,1,3,5-tetramethyl-4-oxo-2,6-diphenylpiperidinium triflate, in acetonitrile efficiently catalyzes one synthetic operational construction of biopertinent hydropyrimidines from respective aldehyde, beta-dicarbonyl, and urea/thiourea building blocks. (C) 2010 Elsevier Ltd. All rights reserved.
Thiel; Deissner, Justus Liebigs Annalen der Chemie, 1959, vol. 622, p. 98,105