3042-21-5Relevant articles and documents
The first chemoselective synthesis of functionalized 3-vinylpyrroles
Trofimov, Boris A.,Demenev, Andrey P.,Sobenina, Lyubov' N.,Mikhaleva, Al'bina I.,Tarasova, Ol'ga A.
, p. 3501 - 3503 (2003)
3-(1-Alkylthio-2-cyano-2-X-ethenyl)pyrroles (X=CN, CONH2, CO2Et) have been synthesized in 28-58% yields by the reaction of pyrrole-3-carbodithioates with CH-acids (malononitrile, cyanoacetamide, cyanoacetate) in the KOH-DMSO system.
CONDENSATION OF KETOXIMES WITH PHENYLACETYLENE
Korostovka, S. E.,Mikhaleva, A. I.,Trofimov, B. A.,Shevchenko, S. G.,Sigalov, M. V.
, p. 406 - 408 (1992)
2-Methyl-5-phenyl and 2,5-diphenylpyrrole and 2-phenyl, Z--3-phenyl, and 4,5,6,7-tetrahydroindole, and 2,4-diphenyl-3,3-dimethyl-5-hydroxypyrroline have been obtained from the reaction of ketoximes with phenylacetylene, catalyzed by KOH-DMSO.
A robust NNP-type ruthenium (II) complex for alcohols dehydrogenation to esters and pyrroles
Chai, Huining,Zhang, Guangyao,Tan, Weiqiang,Ma, Jiping
, (2019/12/03)
A Ru (II) complex bearing pyridyl-based benzimidazole-phosphine tridentate NNP ligand was synthesized and structurally characterized by NMR, IR. The complex can efficiently and selectively catalyze the acceptorless dehydrogenation of primary alcohols to esters under relatively mild conditions and the synthesis of pyrroles by means of the reactions of secondary alcohols and β-amino alcohols through acceptorless deoxygenation condensation.
PHOSPHINE FREE COBALT BASED CATALYST, PROCESS FOR PREPARATION AND USE THEREOF
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Paragraph 0067; 0126-0127, (2020/12/29)
The present invention discloses a phosphine free cobalt based catalyst of formula (I) and a process for preparation thereof. The present invention further discloses a process for the synthesis of aromatic heterocyclic compounds of formula (II) and pyrazine derivative using the phosphine free cobalt based catalyst of formula (I).
Visible-Light Photocatalytic Preparation of 1,4-Ketoaldehydes and 1,4-Diketones from α-Bromoketones and Alkyl Enol Ethers
García-Santos, William H.,Mateus-Ruiz, Jeferson B.,Cordero-Vargas, Alejandro
supporting information, p. 4092 - 4096 (2019/06/17)
A Ru2+-photocatalyzed, visible-light-mediated ATRA reaction for the straightforward preparation of 1,4-ketoaldehydes, 1,4-diketones, and 1,4-ketoesters, which are of difficult access by other means, is reported herein. This method employs readily accessible α-bromoketones and alkyl vinyl ethers as starting materials, allowing the construction of secondary, tertiary, and challenging quaternary centers. In addition, the synthetic usefulness of this method is illustrated by applying it to the construction of substituted pyrroles.
Synthesis of 2,2,5-Trisubstituted 2 H-Pyrroles and 2,3,5-Trisubstituted 1 H-Pyrroles by Ligand-Controlled Site-Selective Dearomative C2-Arylation and Direct C3-Arylation
Yamaguchi, Miyuki,Fujiwara, Sakiko,Manabe, Kei
supporting information, p. 6972 - 6977 (2019/09/03)
Palladium-catalyzed site-selective dearomative C2-arylation of 2,5-diaryl-1H-pyrroles with aryl chlorides was accomplished, and a series of 2,2,5-triaryl-2H-pyrroles were synthesized. In addition, the site selectivity of the reaction was switched by simply changing the ligand, and the direct C3-arylated 2,3,5-triaryl-1H-pyrroles were prepared. The obtained 2,2,5-triaryl-2H-pyrroles could be further transformed into 2,2,5,5-tetraarylpyrrolidines.
General Transition Metal-Free Synthesis of NH-Pyrroles from Secondary Alcohols and 2-Aminoalcohols
Krasniqi, Besir,Geerts, Kayle,Dehaen, Wim
, p. 5027 - 5034 (2019/05/10)
A novel, transition metal-free and one-pot methodology to synthesize various substituted NH-pyrroles from readily available building blocks such as secondary alcohols and 2-aminoalcohols is described. The process is based on the venerable Oppenauer-Woodward oxidation, which uses benzophenone as an inexpensive reagent to achieve oxidation of secondary alcohols under mild condition to ketones, further in situ condensation with aminoalcohol, and oxidative cyclization to the target pyrrole ring. The reaction occurs under basic conditions, and features a broad substrate scope combined with very good tolerance for sensitive functional groups. This method can be used to synthesize various substituted pyrroles useful as a starting material for broad applications.
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.
A Synthetic Methodology for Pyrroles from Nitrodienes
EL-Atawy, Mohamed A.,Ferretti, Francesco,Ragaini, Fabio
, p. 4818 - 4825 (2018/03/27)
Palladium complexes containing the ligand 4,7-dimethoxy-1,10-phenanthroline have been used to catalyze the reductive cyclization of nitrodienes using carbon monoxide as the reductant to give pyrroles. Carbon dioxide was the only stoichiometric byproduct of the reaction. The yields were good and the starting materials can be easily synthesized in two steps by a cross-aldol condensation reaction followed by a Henry reaction. Different substitution patterns are tolerated by this novel synthetic strategy.
A nitrogen-ligated nickel-catalyst enables selective intermolecular cyclisation of β- And γ-amino alcohols with ketones: Access to five and six-membered N-heterocycles
Singh, Khushboo,Vellakkaran, Mari,Banerjee, Debasis
supporting information, p. 2250 - 2256 (2018/05/30)
Owing to the great demand for the synthesis of N-heterocycles, development of new reactions that utilise renewable resources and convert them into key chemicals using non-precious base metal-catalysts is highly desirable. Herein, we demonstrated a sustainable Ni-catalysed dehydrogenative approach for the synthesis of pyrroles, pyridines, and quinolines by the reaction of β- and γ-amino alcohols with ketones via C-N and C-C bond formations in a tandem fashion. A variety of aryl, hetero-aryl, and alkyl ketones having free amine, halide, alkyl, alkoxy, alkene, activated benzyl, and pyridine moieties were converted into synthetically interesting 2,3 and 2,3,5-substituted bicyclic as well as tricyclic N-heterocycles with up to 90% yields. As a highlight, we demonstrated the synthesis of an interesting pyrrole derivative by intermolecular cyclisation of a steroid hormone with phenylalaninol.