89609-67-6Relevant academic research and scientific papers
Synthesis and aminolysis of N,N-diethyl carbamic ester of HOBt derivatives
Khattab, Sherine Nabil,Hassan, Seham Yassin,Hamed, Ezzat Awad,Albericio, Fernando,Ayman, El-Faham
experimental part, p. 75 - 81 (2010/07/15)
The reaction of N,N-diethyl carbamates of 1H-[1,2,3]triazolo[4,5-b]pyridin- 1-ol (4-HOAt) 7, 3H-[1,2,3]triazolo[4,5- b]pyridin-3-ol (7-HOAt) 8, 1H-benzo[d][1,2,3]triazol-1-ol (HOBt) 9, 6-chloro-1H-benzo[d][1,2,3]triazol-1-ol (Cl- HOBt) 10, 6-(trifluoromethyl)-1H-benzo[d][1,2,3]triazol-1-ol (CF3 3-HOBt) 11, and 6-nitro-1H-benzo[d][1,2,3]triazol- 1-ol (NO2 2-HOBt) 12 with morpholine and piperidine in CH3CN underwent acyl nucleophilic substitution to give the corresponding carboxamide derivatives. The reactants and products were identified by elemental analysis, IR and NMR. We measured the kinetics of these reactions spectrophotometrically in CH3 3CN at a range of temperatures. The rates of morpholinolysis and piperidinolysis were found to fit the Hammett equation and correlated with s-Hammett values. The values were 1.44 - 1.21 for morpholinolysis and 1.95 - 1.72 for piperidinolysis depending on the temperature. The Bronsted-type plot was linear with a βlg = -0.49 ± 0.02 and -0.67 ± 0.03. The kinetic data and structure-reactivity relationships indicate that the reaction of 9-12 with amines proceeds by a concerted mechanism. The deviation from linearity of the correlation ?H# vs. ?S# and plot of logkpip vs. logkmorph and Bronsted-type correlation indicate that the reactions of amines with carbamates 7 and 8 is attributed to the electronic nature of their leaving groups.
Synthesis and morpholinolysis of N,N-diethyl carbamate derivatives of 4- HOAt, 7-HOAt and HOBt
Khattab, Sherine N.,Hassan, Seham Y.,Hamed, Ezzat A.,El-Faham, Ayman
, p. 247 - 251 (2008/02/10)
N,N-Diethyl carbamates of 1-hydroxy-7-azabenzotriazole (7-HOAt), 1-hydroxy-4-azabenzotriazole (4-HOAt), 1-hydroxybenzotriazole (HOBt), and 1-hydroxypyrrolidine-2,5-dione have been synthesised. The reactivities of these active esters have been determined by studying the kinetics and mechanism of their morpholinolysis in acetonitrile at different temperatures.
