3042-22-6Relevant articles and documents
HEXACARBONYLMOLYBDENUM- OR NONACARBONYLDIIRON-INDUCED REACTION OF 1,3-OXAZEPINE RING SYSTEM. EVIDENCE FOR THE VALENCE ISOMERIZATION BETWEEN 1,3-OXAZEPINE AND PYRIDINE-2,3-OXIDE
Nitta, Makoto,Kobayashi, Tomoshige
, p. 877 - 880 (1985)
Upon treatment with or , phenyl-substituted 1,3-oxazepines undergo the C-2-O and C-7-O bond cleavage to give pyridine and pyrrole derivatives via a coordinated pyridine-2,3-oxide.
UNEXPECTED LOSS OF FUNCTIONALITY DURING THE TROFIMOV SYNTHESIS OF PYRROLES FROM 4-NITRO AND 4-DIMETHYLAMINOACETOPHENONE OXIMES
Korostova, S. E.,Shevchenko, S. G.,Mikhaleva, A. I.
, p. 1410 (1989)
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Blicke,Powers
, p. 304 (1944)
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C-vinylation of 1-vinylpyrroles with benzoylacetylene on silica gel
Trofimov,Stepanova,Sobenina,Mikhaleva,Ushakov,Elokhina
, p. 1878 - 1882 (2001)
1-Vinylpyrroles readily add to benzoylacetylene on grinding the reagents with silica gel at room temperature to form 2-(E)-(2-benzoylvinyl)-1-vinylpyrroles in 50-84% yield in a regioand stereoselective manner.
Mechanistic Insights into Iron-Catalyzed C-H Bond Activation and C-C Coupling
Brewer, Samantha M.,Schwartz, Timothy M.,Mekhail, Magy A.,Turan, Lara S.,Prior, Timothy J.,Hubin, Timothy J.,Janesko, Benjamin G.,Green, Kayla N.
, p. 2467 - 2477 (2021)
Iron-catalyzed C-C coupling reactions of pyrrole provide a unique alternative to the traditional Pd-catalyzed counterpart. However, many details regarding the actual mechanism remain unknown. A series of macrocyclic iron(III) complexes were used to evaluate specifics related to the role of O2, radicals, and μ-oxodiiron-complex participation in the catalytic cycle. It was determined that the mononuclear tetra-Azamacrocyclic complex is a true catalyst and not a stoichiometric reagent, while more than one equivalent of a sacrificial oxidant is needed. Furthermore, the reaction does not proceed through an organic radical pathway. μ-Oxodiiron complexes are not involved in the main catalytic pathway, and the dimers are, in fact, off-cycle species that decrease catalytic efficiency.
Intramolecular H-atom abstraction in γ-azido-butyrophenones: Formation of 1,5 ketyl iminyl radicals
Muthukrishnan, Sivaramakrishnan,Sankaranarayanan, Jagadis,Klima, Rodney F.,Pace, Tamara C. S.,Bohne, Cornelia,Gudmundsdottir, Anna D.
, p. 2345 - 2348 (2009)
Photolysis of γ-azidobutyrophenone derivatives yields 1,4 ketyl biradicals via intramolecular H-atom abstraction. The 1,4 ketyl biradicals expel a nitrogen molecule to form 1,5 ketyl iminyl biradicals, which decay by ring closure to form a new carbon-nitr
2-phenylpyrrole: One-pot selective synthesis from acetophenone oxime and acetylene by a Trofimov reaction
Mikhaleva,Petrova,Sobenina
, p. 1367 - 1371 (2012)
We have developed a technologically orientated, one-pot way of synthesis of high purity 2-phenylpyrrole in 74% yield by treatment of acetophenone oxime with acetylene in the KOH-DMSO system. The reaction is carried out at 135-150°C under an acetylene atmospheric pressure. The synthesis was performed in laboratory (glass apparatus) and in a large scale (10 l reaction vessel).
Regioselective C3-Phosphonation of Free Indoles via Transition-Metal-Free Radical/Hydrolysis Cascade
Guo, Shengmei,Jie, Kun,Zhang, Zhebin,Fu, Zhengjiang,Cai, Hu
, p. 1808 - 1814 (2019)
The selectivity is of great importance for the preparation of molecules in organic chemistry. Herein, a novel method to enable the highly regioselective C3-phosphonation of free indoles has been developed. This transformation involves a radical and a hydrolysis procedure, and tolerates a range of functional groups, which gives an efficient route toward the 1H-indol-3 – ylphosphonic acid monoesters in one step.
Asymmetric Alkylation of Ketones Catalyzed by Engineered TrpB
Arnold, Frances H.,Buller, Andrew R.,Dunham, Noah P.,Straathof, Sabine,Turi, Soma,Watkins-Dulaney, Ella J.
supporting information, p. 21412 - 21417 (2021/08/20)
The β-subunit of tryptophan synthase (TrpB) catalyzes a PLP-mediated β-substitution reaction between indole and serine to form L-Trp. A succession of TrpB protein engineering campaigns to expand the enzyme's nucleophile substrate range has enabled the biocatalytic production of diverse non-canonical amino acids (ncAAs). Here, we show that ketone-derived enolates can serve as nucleophiles in the TrpB reaction to achieve the asymmetric alkylation of ketones, an outstanding challenge in synthetic chemistry. We engineered TrpB by directed evolution to catalyze the asymmetric alkylation of propiophenone and 2-fluoroacetophenone with a high degree of selectivity. In reactions with propiophenone, preference for the opposite product diastereomer emerges over the course of evolution, demonstrating that full control over the stereochemistry at the new chiral center can be achieved. The addition of this new reaction to the TrpB platform is a crucial first step toward the development of efficient methods to synthesize non-canonical prolines and other chirally dense nitrogen heterocycles.
Concurrent Formation of N-H Imines and Carbonyl Compounds by Ruthenium-Catalyzed C-C Bond Cleavage of β-Hydroxy Azides
Lee, Jeong Min,Bae, Dae Young,Park, Jin Yong,Jo, Hwi Yul,Lee, Eunsung,Rhee, Young Ho,Park, Jaiwook
, p. 4608 - 4613 (2020/06/05)
A commercial cyclopentadienylrutenium dicarbonyl dimer ([CpRu(CO)2]2) efficiently catalyzes the formation of N-H imines and carbonyl compounds simultaneously from β-hydroxy azides via C-C bond cleavage under visible light. Density functional theory calculations for the cleavage reaction support the mechanism involving chelation of alkoxy azide species and liberation of nitrogen as the driving force. The synthetic utility of the reaction was demonstrated by a new amine synthesis promoted by chemoselective allylation of imine and synthesis of isoquinoline.