Synthesis and Aminolysis of N,N-Diethyl Carbamic Ester of HOBt Derivatives

Abstract

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] and 6-nitro-1H-benzo[d][1,2,3]triazol-1-ol (NO2-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 CH3CN at a range of temperatures. The rates of morpholinolysis and piperidinolysis were found to fit the Hammett equation and correlated with σ-Hammett values. The values were 1.44 -1.21 for morpholinolysis and 1.95 -1.72 for piperidinolysis depending on the temperature. The Brønsted-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 Brønsted-type correlation indicate that the reactions of amines with carbamates 7 and 8 is attributed to the electronic nature of their leaving groups.

Experimental and theoretical approaches to the study of the reactivity and mechanism of the substitution of phenyl 1‐(2,4‐dinitronaphthyl) ether with anilines derivatives

“…14 The mechanisms of few aromatic nucleophilic substitution reactions have been investigated by performing theoretical calculations by other methods. 12,15 As extension to our previous work in the field of nucleophilic aryl substitution reaction, [16][17][18][19][20][21][22][23][24][25][26][27][28] this work suggests a mechanism for the reaction of phenyl 1-(2,4-dinitronaphthyl) ether (1) with 3-and 4-substituted aniline derivatives (2a-f) in dimethyl sulfoxide (DMSO) (Equation 1). The effect of substituents in the nucleophile on the rate was also discussed, and Hammett and Brönsted correlations were examined.…”

“…As extension to our previous work in the field of nucleophilic aryl substitution reaction, 16‐28 this work suggests a mechanism for the reaction of phenyl 1‐(2,4‐dinitronaphthyl) ether ( 1 ) with 3‐ and 4‐substituted aniline derivatives (2a‐f) in dimethyl sulfoxide (DMSO) (Equation 1). The effect of substituents in the nucleophile on the rate was also discussed, and Hammett and Brönsted correlations were examined.…”

Understanding the reaction mechanism of the regioselective piperidinolysis of aryl 1-(2,4-dinitronaphthyl) ethers in DMSO: Kinetic and DFT studies

“…Several studies have been reported that aryl 1-(2,4-dinitronaphthyl) ether (1a-h) were considered as good substrates toward SNAr reactions. [20][21][22][23][24][25][26][27][28][29][30][31][32][33] This is because 2,4-dinitro groups with respect to 1-chloro substituent in one of the two rings of naphthalene made it susceptible toward nucleophilic substitution, and stable activated complex(s) is formed. 34,35 In the present study, kinetic of the reaction of aryl 1-(2,4-dinitronaphthyl) ether (1a-h) (Ar = a, X = H; b, X = 4-OCH 3 ; c, X = 4-CH 3 ; d, X = 3-CH 3 ; e, X = 3-OCH 3; f, X = 4-Cl; g, X = 3-Cl; and h, X = 4-NO 2 ) with piperidine (2) in DMSO at 25 o C was examined Scheme 1.…”

Aminolysis of 1-(1-Hydroxybenzotriazolyl)-2,4-dinitrobenzene and 2-(1-Hydroxybenzotriazolyl)-5-nitropyridine

“…In continuation of our studies in the field of nucleophilic aryl and acyl reactions [30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45], we addressed kinetic studies of the leaving group ability of 1-hydroxybenzotriazole (HOBt) in two example: 1-(1-hydroxybenzotriazolyl)-2,4-dinitro-benzene 1 and 2-(1-hydroxy-benzotriazolyl) 5-nitro-pyridine 2. The kinetic studies of 1 and 2 with different amines such as morpholine, cyclohexylamine and aniline in methanol (MeOH), acetonitrile (AN) and toluene (Tol) will be measured.…”