<i>N</i>,<i>N</i>′,<i>N</i>,<i>N</i>′-TETRABROMO-BENZENE-1,3-DISULFONYLAMIDE AS A NOVEL REAGENT FOR OXIDATIVE AROMATIZATION OF 1,3,5-TRISUBSTITUTED PYRAZOLINES UNDER HETEROGENEOUS AND SOLVENT-FREE CONDITIONS
1,3,5-Trisubstituted pyrazolines were converted to the corresponding pyrazoles in good yields under heterogeneous and solvent-freeconditions by N,N′,N,N′-tetrabromo-benzene-1,3-disulfonylamide [TBBDA] at ambient temperature.
1,3,5-Trisubstituted pyrazolines to pyrazoles are carried out efficiently in the presence of new reagents N,N,N',N'-tetrabromo-benzene-1,3-disulfonylamine [TBBDA] and N,N'-dibromo-N,N'-1,2-ethanediylbis-(p-toluenesulphonamide) [BNBTS] in solvent-freeconditions with catalytic amounts of SiO 2 under microwave irradiation in high yields.
Microwave-assisted Aromatization of 1,3,5-Trisubstituted 2-Pyrazolines by Silica-supported N-Bromosuccinimide as a Useful Reagent under Solvent Free ‘Dry’ Condition
作者:Davood Azarifar、Behrooz Maleki
DOI:10.3987/com-04-10276
日期:——
An efficient aromatization of 1,3,5-trisubstituted2-pyrazolines to their corresponding pyrazoles by NBS was carried out under microwave irradiation and solvent-free conditions in moderate yields. It has also been observed that, by activating the NBS reagent on silica gel as a support the reaction times can be dramatically reduced and good yields are obtained.
Microwave‐Assisted Aromatization of 1,3,5‐Trisubstituted 2‐Pyrazolines by Bi(NO<sub>3</sub>)<sub>3</sub> · 5H<sub>2</sub>O, as a Novel and Convenient Oxidizing Agent
作者:Davood Azarifar、Behrooz Maleki
DOI:10.1080/00397910500214136
日期:2005.10
Abstract Bismuth(III) nitrate pentahydrate, Bi(NO3)3 · 5H2O, has been used as a mild, efficient, and inexpensive oxidant for the oxidative aromatization of several 1,3,5‐trisubstituted 2‐pyrazolines to pyrazoles in acetic acid under microwave irradiation with good to excellent yields.
Tricholoroisocyanuric Acid as a Useful Reagent in Microwave-assisted Aromatization of 1,3,5-Trisubstituted 2-Pyrazolines
作者:Davood Azarifar、Behrooz Maleki
DOI:10.1002/jccs.200500174
日期:2005.12
An efficient aromatization of 1,3,5-trisubstituted2-pyrazolines to their corresponding pyrazoles has been performed by tricholoroisocyanuricacid [TCCA] under microwave irradiation in excellent yields. It has been observed that the reactions occur more rapidly under microwave irradiation conditions, and the amount of the reagent TCCA consumed is considerably reduced to afford better yields when compared