Hofmann elimination of heterocycles containing bridgehead hydrazines. I. 2,6-Benzodiazonine and dibenzo[c,h][1,6]diazecine derivatives

1969 ◽  
Vol 34 (9) ◽  
pp. 2715-2720 ◽  
Author(s):  
Paul Aeberli ◽  
William J. Houlihan
Keyword(s):  
Hofmann Elimination

Hofmann elimination

2014 ◽  
pp. 318-318
Author(s):  
Jie Jack Li
Keyword(s):  
Hofmann Elimination

scholarly journals Solvating Alkylamine Hofmann Elimination in Zeolites Through Cooperative Adsorption

2021 ◽  
Author(s):  
Han Chen ◽  
Omar Abdelrahman
Keyword(s):  
Direct Measurement ◽  
Bronsted Acid ◽  
Brønsted Acid ◽  
Elimination Kinetics ◽  
Al Content ◽  
Cooperative Adsorption ◽  
Brönsted Acid ◽  
Tert Butylamine ◽  
The Impact ◽  
Hofmann Elimination

<p>A kinetic investigation of the vapor phase Hofmann elimination of tert-butylamine over H-ZSM-5 reveals a carbocation mediated E1-like mechanism, where isobutene and ammonia are exclusively produced over Brønsted acid sites. Hofmann elimination kinetics are found to be insensitive to Al content or siting, varying only with alkylamine carbocation stability (r<sub>tertiary</sub> > r<sub>secondary</sub> > r<sub>primary</sub>). Under conditions of complete tert-butylamine surface coverage, experimentally measurable apparent kinetics are directly equivalent to the intrinsic kinetics of the rate determining unimolecular surface elimination. The direct measurement of elementary step kinetics served as a water-free reactive probe, providing a direct measurement of the impact of water on solid Brønsted acid catalyzed chemistries at a microscopic level. Over a range of temperatures (453‒513 K) and tert-butylamine partial pressures (6.8×10<sup>-2</sup>‒6.8 kPa), water reversibly inhibits the rate of Hofmann elimination. Despite expected changes in aluminosilicate hydrophobicity, the water-induced inhibition is found to be insensitive to Al content, demonstrated to be due to one water molecule per Brønsted acid site. Regardless of the significant reduction in the rate of Hofmann elimination, kinetic interrogations and operando spectroscopic measurements reveal that the coverage of TBA adsorbed on H-ZSM-5 is unaltered in the presence of water. Cooperative adsorption between the tert-butylammonium surface reactant and water adsorbed on a neighboring framework oxygen is proposed to be responsible for the observed rate inhibition, the surface dynamics of which is quantitatively captured through kinetic modeling of experimental rate measurements.</p>

THE CONFORMATIONAL ANALYSIS AND REACTION MECHANISM FOR HOFMANN ELIMINATION OF QUATERNARY AMMONIUM HYDROXIDES

1989 ◽  
Vol 5 (04) ◽  
pp. 398-402
Author(s):  
Xu Xiaojie ◽  
◽  
Yao Zhengui ◽  
Ye Xiulin ◽  
Tang Youqi ◽  
...  
Keyword(s):  
Reaction Mechanism ◽  
Conformational Analysis ◽  
Quaternary Ammonium ◽  
Hofmann Elimination

Synthesis of Thieno[b]quinolizidines and Hofmann Elimination on Methiodides Derivatives

1998 ◽  
Vol 28 (6) ◽  
pp. 949-956 ◽  
Author(s):  
Dusan Berkes ◽  
Pierre Netchitaïlo ◽  
Jean Morel ◽  
Bernard Decroix
Keyword(s):  
Hofmann Elimination

Wittig modification of the Hofmann elimination reaction. Evidence for an .alpha.',.beta. mechanism

1972 ◽  
Vol 94 (24) ◽  
pp. 8608-8610 ◽  
Author(s):  
Robert D. Bach ◽  
Kenneth W. Bair ◽  
Denis Andrzejewski
Keyword(s):  
Elimination Reaction ◽  
Alpha Beta ◽  
Hofmann Elimination

Elimination reactions. V. Steric effects in Hofmann elimination

1975 ◽  
Vol 97 (15) ◽  
pp. 4323-4327 ◽  
Author(s):  
James L. Coke ◽  
G. Dale Smith ◽  
George H. Britton
Keyword(s):  
Steric Effects ◽  
Elimination Reactions ◽  
Hofmann Elimination

scholarly journals Electrochemical synthesis of copper(i) acetylides via simultaneous copper ion and catalytic base electrogeneration for use in click chemistry

RSC Advances ◽  
2019 ◽  
Vol 9 (50) ◽  
pp. 29300-29304
Author(s):  
Peter W. Seavill ◽  
Katherine B. Holt ◽  
Jonathan D. Wilden
Keyword(s):  
Click Chemistry ◽  
Quaternary Ammonium ◽  
Electrochemical Synthesis ◽  
Copper Ion ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Copper Oxidation ◽  
Hofmann Elimination

We report an efficient and sustainable electrochemical synthesis of copper(i) acetylides using simultaneous copper oxidation and Hofmann elimination of quaternary ammonium salts.

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