- L -Proline: An Efficient Organocatalyst for the Synthesis of 5-Substituted 1 H -Tetrazoles via [3+2] Cycloaddition of Nitriles and Sodium Azide
-
A simple and efficient route for the synthesis of a series of 5-substituted 1 H -tetrazoles using l -proline as a catalyst from structurally diverse organic nitriles and sodium azide is reported. The prominent features of this environmentally benign, cost effective, and high-yielding l -proline-catalyzed protocol includes simple experimental procedure, short reaction time, simple workup, and excellent yields making it a safer and economical alternative to hazardous Lewis acid catalyzed methods. The protocol was successfully applied to a broad range of substrates, including aliphatic and aryl nitriles, organic thiocyanates, and cyanamides.
- Bhagat, Saket B.,Telvekar, Vikas N.
-
-
Read Online
- Synthesis of arylaminotetrazoles by ZnCl2/AlCl 3/silica as an efficient heterogeneous catalyst
-
Arylaminotetrazoles were efficiently synthesized from secondary arylcyanamides by application of ZnCl2/AlCl3/silica as a reusable heterogeneous Lewis acid catalyst. 5-Arylamino-1H-tetrazoles can be obtained from arylcyanamides carryi
- Habibi, Davood,Nasrollahzadeh, Mahmoud
-
experimental part
p. 925 - 930
(2012/08/07)
-
- Solvent-free preparation of arylaminotetrazole derivatives using aluminum(III) hydrogensulfate as an effective catalyst
-
An efficient and simple method for the preparation of 5-arylamino-1H- tetrazole and 1-aryl-5-amino-1H-tetrazole derivatives is reported using aluminum(III) hydrogensulfate (Al(HSO4)3) as an effective heterogeneous catalyst from secon
- Khamooshi, Ferydoon,Modarresi-Alam, Ali Reza
-
experimental part
p. 892 - 896
(2011/11/13)
-
- Silica-supported ferric chloride (FeCl3-SiO2): An efficient and recyclable heterogeneous catalyst for the preparation of arylaminotetrazoles
-
An efficient method for preparation of 5-arylamino-1H-tetrazole and 1-aryl-5-amino-1H-tetrazole derivatives is reported using FeCl 3-SiO2 as an effective heterogeneous catalyst. Generally, when the substituent in arylcyanamide is a strongly electron-withdrawing group, the position of the equilibrium would shift toward 5-arylamino-1H-tetrazole, whereas with an electron-releasing substituent, the position of the equilibrium would shift toward 1-aryl-5-amino-1H-tetrazole. Copyright Taylor & Francis Group, LLC.
- Habibi, Davood,Nasrollahzadeh, Mahmoud
-
experimental part
p. 3159 - 3167
(2010/11/18)
-
- On the Physicochemical Characterization of 5-Amino-1-aryl-1H-tetrazoles: Electronic Molecule Parameters from the Thermal Isomerization into 5-Arylamino-1H-tetrazoles
-
The known thermal isomerization of 5-amino-1-aryl-1H-tetrazoles (A) into corresponding 5-arylamino-1H-tetrazoles (HB) was used to derive physicochemical parameters characterizing the electronic substituent effect on isomerism and dissociation equilibria. For a series of 26 tetrazoles A as starting materials the equilibrium constants (pKi) of isomerization in boiling ethylene glycol at 197°C and the dissociation constants (pKa) of the NH-acidic tetrazoles HB were determined by potentiometric titration of rapidly cooled equilibrium mixtures in water and ethanol/water with KOH at 25°C. The pK values are closely correlated with Hammett's electronic substituent constants σ and can be used as electronic molecule parameters in QSAR or QSPR (QSAR = quantitative structure-activity relationship; QSPR = quantitative structure-property relationship) studies.
- Schelenz, Thomas,Schaefer, Wieland
-
p. 197 - 200
(2007/10/03)
-