- A solvent-free manganese(II) -catalyzed Clauson-Kaas protocol for the synthesis of N-aryl pyrroles under microwave irradiation
-
The first manganese-catalyzed modified Clauson-Kaas reaction for N-substituted pyrrole synthesis using 2,5-dimethoxytetrahydrofuran with variously substituted aromatic amines has been developed (up to 89% yield). This interesting neat strategy is free from additives including co-catalysts, ligands, and acids. Relatively low cost, environmentally benign, and handy Mn(NO3)2·4H2O is employed as the catalyst under microwave conditions with a very short reaction time (20?min). The above qualities attest to the green nature of this reaction.
- Rohit, Kizhakkekuttu Radhakrishnan,Meera, Gopinadh,Anilkumar, Gopinathan
-
supporting information
p. 194 - 200
(2021/10/12)
-
- Transition-metal-free hydrogenation of aryl halides: From alcohol to aldehyde
-
A transition-metal-and catalyst-free hydrogenation of aryl halides, promoted by bases with either aldehydes or alcohols, is described. One equivalent of benzaldehyde affords an equal yield as that of 0.5 equiv of benzyl alcohol. The kinetic study reveals that the initial rate of PhCHO is much faster than that of BnOH, in the ratio of nearly 4:1. The radical trapping experiments indicate the radical nature of this reaction. Based on the kinetic study, trapping and KIE experiments, and control experiments, a tentative mechanism is proposed. As a consequence, a wide range of (hetero)aryl iodides and bromides were efficiently reduced to their corresponding (hetero)arenes. Thus, for the first time, aldehydes are directly used as hydrogen source instead of other well-established alcohol-hydrogen sources.
- Zheng, Hong-Xing,Shan, Xiang-Huan,Qu, Jian-Ping,Kang, Yan-Biao
-
supporting information
p. 5114 - 5117
(2017/11/07)
-
- L-(+)-Tartaric acid and choline chloride based deep eutectic solvent: An efficient and reusable medium for synthesis of N-substituted pyrroles via Clauson-Kaas reaction
-
l-(+)-Tartaric acid-choline chloride based deep eutectic solvent has been found to be an effective promoted medium for Clauson-Kaas reaction of aromatic amines and 2,5-dimethoxytetrahydrofuran. Structurally diverse N-substituted pyrroles were obtained in high to excellent yields under mild conditions. The deep eutectic solvent is inexpensive, non-toxic, reusable and biodegradable.
- Wang, Ping,Ma, Fei-Ping,Zhang, Zhan-Hui
-
p. 259 - 262
(2014/11/07)
-
- Squaric acid catalyzed simple synthesis of N-substituted pyrroles in green reaction media
-
An operationally simple and efficient protocol for squaric acid catalyzed synthesis of N-substituted pyrroles via the reaction of 2,5- dimethoxytetrahydrofuran and 2,5-hexandione with aryl amines in green reaction media (water, deep eutectic solvent, and polyethylene glycol) under ultrasound irradiation or thermal conditions in good to excellent yields has been developed.
- Azizi, Najmadin,Davoudpour, Anahita,Eskandari, Farshid,Batebi, Ehlham
-
p. 405 - 409
(2013/05/09)
-
- A recyclable magnetic nanoparticles supported antimony catalyst for the synthesis of N-substituted pyrroles in water
-
A new magnetic nanoparticle-supported antimony catalyst was prepared and evaluated as a recoverable catalyst for Clauson-Kaas reaction. The reaction proceeds efficiently in aqueous medium to give the corresponding N-substituted pyrroles in high yield. The immobilized catalyst could be easily recovered by magnetic separation and recycled for six times without significant loss of its catalytic activity.
- Ma, Fei-Ping,Li, Pei-He,Li, Bao-Le,Mo, Li-Ping,Liu, Ning,Kang, Hui-Jun,Liu, Ya-Nan,Zhang, Zhan-Hui
-
-
- Iron-catalyzed inexpensive and practical synthesis of N-substituted pyrroles in water
-
An operationally simple, practical, and economical protocol for iron(III) chloride catalyzed Paal-Knorr pyrrole synthesis in water in good to excellent yields has been developed. Several N-substituted pyrroles are readily prepared from the reaction of 2,5-dimethoxytetrahydrofuran and aryl/alkyl, sulfonyl and acyl amines under very mild reaction conditions. Georg Thieme Verlag Stuttgart.
- Azizi, Najmedin,Khajeh-Amiri, Alireza,Ghafuri, Hossein,Bolourtchian, Mohammad,Saidi, Mohammad Reza
-
experimental part
p. 2245 - 2248
(2009/12/03)
-
- Scandium triflate-catalysed synthesis of N-substituted pyrroles from amine and 2,5-dimethoxytetrahydrofuran
-
The Clauson-Kass pyrrole synthesis catalysed by scandium triflate afforded N-substituted 2- and 3-unsubstituted pyrroles with yields ranged from good to excellent. Aromatic amines, heteroaomatic amines, 4-methylbenzenesulfonamide and 2-chlorobenzamide are good substrates in this transformation.
- Zuo, Bing,Chen, Jiuxi,Liu, Miaochang,Ding, Jinchang,Wu, Huayue,Su, Weike
-
experimental part
p. 14 - 16
(2009/09/25)
-
- Polyaromatic amines. Part 3: Synthesis of poly(diarylamino)styrenes and related compounds
-
The title compounds were synthesised and characterised as part of a study into new aromatic amines for charge transporting materials. Compounds 12-16, 20-24 and 27-34 are alkene linked triarylamines, compounds 35-36 are hydrazone derivatives and compounds 38-41 are pyrrole substituted triarylamines. Each compound was characterised by cyclic voltammetry.
- Plater, M. John,Jackson, Toby
-
p. 4673 - 4685
(2007/10/03)
-
