50691-34-4Relevant articles and documents
Volatiles from the Psychrotolerant Bacterium Chryseobacterium polytrichastri
Lauterbach, Lukas,Dickschat, Jeroen S.
, p. 3608 - 3617 (2020/09/22)
The flavobacterium Chryseobacterium polytrichastri was investigated for its volatile profile by use of a closed-loop stripping apparatus (CLSA) and subsequent GC-MS analysis. The analyses revealed a rich headspace extract with 71 identified compounds. Compound identification was based on a comparison to library mass spectra for known compounds and on a synthesis of authentic standards for unknowns. Important classes were phenylethyl amides and a series of corresponding imines and pyrroles.
Sustainable Manganese-Catalyzed Solvent-Free Synthesis of Pyrroles from 1,4-Diols and Primary Amines
Borghs, Jannik C.,Lebedev, Yury,Rueping, Magnus,El-Sepelgy, Osama
supporting information, p. 70 - 74 (2019/01/11)
A general and selective metal-catalyzed conversion of biomass-derived primary diols and amines to the highly valuable 2,5-unsubstituted pyrroles has been developed. The reaction is catalyzed by a stable nonprecious manganese complex (1 mol %) in the absence of organic solvents whereby water and molecular hydrogen are the only side products. The manganese catalyst shows unprecedented selectivity, avoiding the formation of pyrrolidines, cyclic imides, and lactones.
Grinding solvent-free paal-knorr pyrrole synthesis on smectites as recyclable and green catalysts
Marvi, Omid,Nahzomi, Hossein Taherpour
, p. 139 - 147 (2018/04/23)
An environmentally benign method for the synthesis of N-substituted pyrroles from one-pot solvent-free condensation reaction of 2,5-hexanedione with various primary amines (Paal-Knorr pyrrole synthesis) on smectite clays as green and reusable heterogeneous Lewis acid catalysts is presented. The use of nontoxic, inexpensive, easily available and reusable catalysts under solvent-free conditions make this protocol practical, environmentally friendly and economically attractive.
Chemoselective Synthesis of Amines from Ammonium Hydroxide and Hydroxylamine in Continuous Flow
Audubert, Clément,Bouchard, Alexanne,Mathieu, Gary,Lebel, Hélène
, p. 14203 - 14209 (2019/01/21)
The chemoselective amination of alkyl bromides and chlorides with aqueous ammonia and hydroxylamine was achieved in continuous flow to produce primary ammonium salts and hydroxylamines in high yields. An in-line workup was designed to isolate the corresponding primary amine, which was also telescoped in further reactions, such as acylation and Paal-Knorr pyrrole synthesis. Monosubstituted epoxides are also compatible with the reaction conditions.
Acceptorless Dehydrogenative Coupling Using Ammonia: Direct Synthesis of N-Heteroaromatics from Diols Catalyzed by Ruthenium
Daw, Prosenjit,Ben-David, Yehoshoa,Milstein, David
supporting information, p. 11931 - 11934 (2018/09/27)
The synthesis of N-heteroaromatic compounds via an acceptorless dehydrogenative coupling process involving direct use of ammonia as the nitrogen source was explored. We report the synthesis of pyrazine derivatives from 1,2-diols and the synthesis of N-substituted pyrroles by a multicomponent dehydrogenative coupling of 1,4-diols and primary alcohols with ammonia. The acridine-based Ru-pincer complex 1 is an effective catalyst for these transformations, in which the acridine backbone is converted to an anionic dearomatized PNP-pincer ligand framework.
Efficient synthesis of substituted pyrroles through Pd(OCOCF3)2-catalyzed reaction of 5-hexen-2-one with primary amines
Chen, Xi,Yang, Meng,Zhou, Min
supporting information, p. 5215 - 5218 (2016/11/11)
An efficient and facile Pd(OCOCF3)2-catalyzed one-pot cascade protocol has been developed for the synthesis of multiple substituted pyrroles in good to excellent yields. Unlike the reported method starting from the 2-alkenal-1,3-carbonyl compounds, the process utilizes the less reactive 5-hexen-2-one and the method has great potential as a complement to the current developed methods.
Direct Synthesis of Pyrroles by Dehydrogenative Coupling of Diols and Amines Catalyzed by Cobalt Pincer Complexes
Daw, Prosenjit,Chakraborty, Subrata,Garg, Jai Anand,Ben-David, Yehoshoa,Milstein, David
supporting information, p. 14373 - 14377 (2016/11/11)
Herein, the first example of base-metal-catalyzed dehydrogenative coupling of diols and amines to selectively form functionalized 1,2,5-substituted pyrroles liberating water and hydrogen gas as the sole by-products is presented. The reaction is catalyzed
The Paal-Knorr reaction revisited. A catalyst and solvent-free synthesis of underivatized and N-substituted pyrroles
Cho, Hyejin,Madden, Richard,Nisanci, Bilal,T?r?k, Bla
, p. 1088 - 1099 (2015/03/04)
A new, modified synthesis of pyrroles is described. The reaction of 2,5-hexandione with a variety of amines yielded the expected pyrrole analogues in excellent yields. The reactions were carried out under the ultimate green conditions excluding both catalyst and solvent applying simple stirring at room temperature. The variety of amines include aqueous ammonium hydroxide for the synthesis of pyrroles with a free NH group, and benzylamines, anilines and phenylene-diamines for the synthesis of several N-derivatized pyrroles. The reaction also occurs efficiently with a variety of 1,4-diketones, although the reaction rates and yields are lower for the diketones that do not possess terminal methyl group(s). This journal is
Paal-Knorr pyrrole synthesis using recyclable amberlite IR 120 acidic resin: A green approach
Devi, Aarti,Shallu,Sharma,Singh, Jasvinder
experimental part, p. 1480 - 1488 (2012/05/05)
Amberlite IR 120 acidic resin, a polymer matrix, has been demonstrated as a catalyst for Paal-Knorr condensation of 2,5-hexadione with primary amines under solvent-free conditions. This is an efficient, mild, and green methodology for N-substituted pyrrole derivatives. Copyright Taylor & Francis Group, LLC.
Approach to synthesis of Β-enamino ketones and pyrroles catalyzed by gallium(III) triflate under solvent-free conditions
Chen, Jiuxi,Yang, Xiaoliang,Liu, Miaochang,Wu, Huayue,Ding, Jinchang,Su, Weike
experimental part, p. 4180 - 4198 (2010/01/15)
Metal triflates have been used to catalyze synthesis of-enamino ketones or pyrroles from amines and 1,3-dicarbonyl or 1,4-dicarbonyl compounds under solvent-free conditions, respectively. Among different metal triflates screened, 0.5mol% Ga(OTf)3 efficiently promoted the reactions to give excellent yields. In addition, the catalyst could be recovered easily after the reactions and reused without evident loss in activity.
