Results 181 to 190 of about 13,292 (250)
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Organic Letters, 2020
A Cu-catalyzed asymmetric ring-opening reaction of five-membered diaryliodonium salts and oximes is introduced. The reactions undergo selective N-arylation of oximes and provide an efficient protocol for the synthesis of atropisomeric nitrones.
Wenjing Guo, J. Gu, Z. Gu
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A Cu-catalyzed asymmetric ring-opening reaction of five-membered diaryliodonium salts and oximes is introduced. The reactions undergo selective N-arylation of oximes and provide an efficient protocol for the synthesis of atropisomeric nitrones.
Wenjing Guo, J. Gu, Z. Gu
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Tetrahedron, 1978
Abstract Reactions of 3,4-dihydroisoquinoline N-oxide ( 1 ) with carbomethoxymethyldiphenylphosphine oxide ( 13 ) and cyanomethyldiphenylphosphine oxide ( 14 ) lead both in 1,2-dimethoxyethane (DME) and in t-BuOH mostly to enamines 6 and 7 respectively.
Eli Breuer, Shmuel Zbaida
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Abstract Reactions of 3,4-dihydroisoquinoline N-oxide ( 1 ) with carbomethoxymethyldiphenylphosphine oxide ( 13 ) and cyanomethyldiphenylphosphine oxide ( 14 ) lead both in 1,2-dimethoxyethane (DME) and in t-BuOH mostly to enamines 6 and 7 respectively.
Eli Breuer, Shmuel Zbaida
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Journal of Organic Chemistry, 2020
New derivatives of α-phenyl-N-tert-butyl nitrone (PBN) bearing a hydroxyl, an acetate or an acetamide substituent on the N-tert-butyl moiety and para-substituted phenyl or naphthlyl moieties were synthesized.
Anaïs Deletraz +7 more
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New derivatives of α-phenyl-N-tert-butyl nitrone (PBN) bearing a hydroxyl, an acetate or an acetamide substituent on the N-tert-butyl moiety and para-substituted phenyl or naphthlyl moieties were synthesized.
Anaïs Deletraz +7 more
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Cyclic nitrones. I. Reactions of α-keto nitrones at nitrone carbon
Australian Journal of Chemistry, 1967The chemistry of 3,4,5,6-tetrahydro-3-oxopyridine 1-oxides has been studied with respect to: reaction with hydrazine-the 6,6-dimethyl compound (IV) gave a hydrazone (VII) by ring contraction following initial attack at C 2; (ii)(ii) 2-arylation with diazonium salts, e.g.
L Subrahmanyan, Rfc Brown, CP Whittle
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Nitrones and oxaziridines. VIII. Cycloaddition reactions of nitrones with isothiocyanates
Australian Journal of Chemistry, 1973Whereas nitrones undergo cycloaddition to the C=N double bond of phenyl isothiocyanate, predominant addition to the C=S double bond of substituted phenyl isothiocyanates, methyl isothiocyanate and benzoyl isothiocyanate occurs. However, these cycloadducts are not stable but undergo fragmentation usually with the formation of thioamides and isocyanates.
Dsc Black, Keith G. Watson
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Nitrones. Part III. Photolysis of cyclic nitrones
Journal of the Chemical Society C: Organic, 1966Ultraviolet irradiation of 2-substituted 1-pyrroline 1-oxides yielded corresponding bicyclic oxaziridines. Prolonged irradiation of the 3,3,5-trimethyl-6-oxa-1-azabicyclo[3,1,0]hexane gave an N-acetylazetidine and a pyrroline. Acid hydrolyses of 2,2,5- and 3,3,5-trimethyl-6-oxa-1-azabicyclo[3,1,0]hexane yielded acetonylacetone and 3,3-dimethylpentan-5 ...
L. S. Kaminsky, M. Lamchen
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C−H Reactivity of the α‐Position in Nitrones and Nitronates
Advanced Synthesis & Catalysis, 2019AbstractThe review summarizes the chemistry of nitrones and nitronates in the context of the C−H reactivity of their α‐carbon atoms. Electrophilic, nucleophilic and radical reactions leading to functionalization of the α‐position are described. Examples of the application of these processes in total synthesis are outlined.magnified image
Alexey Yu. Sukhorukov +1 more
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Cycloadditions of Trans‐Cyclooctenes and Nitrones as Tools for Bioorthogonal Labelling
ChemBioChem, 2020Trans‐cyclooctenes (TCOs) represent interesting and highly reactive dipolarophiles for organic transformations including bioorthogonal chemistry. Herein we show that TCOs react rapidly with nitrones and that these reactions are bioorthogonal.
Kaitlyn D. Margison +3 more
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Studies on the chemistry of the chiral nitronic acid and nitronic esters
Tetrahedron: Asymmetry, 1997Abstract Some new chemistry of the chiral nitronic acid and nitronic esters is described. Conversions with retention of configuration are found among the chiral nitronic acid, oxime, nitronic esters and O -alkyloximes. α,β-Elimination reactions of nitronic esters are observed for the first time. Novel and enantiopure chiral bisheterocyclic compounds
Cheng-Lie Yin, Fu-An Kang
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Angewandte Chemie
Herein, we have synthesized multifunctionalized 2-oxa-3-azabicyclo[3.1.1]heptanes, which are considered potential bioisosteres for meta-substituted arenes, through Eu(OTf)3-catalyzed formal dipolar [4π+2σ] cycloaddition of bicyclo[1.1.0]butanes with ...
Jian Zhang +4 more
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Herein, we have synthesized multifunctionalized 2-oxa-3-azabicyclo[3.1.1]heptanes, which are considered potential bioisosteres for meta-substituted arenes, through Eu(OTf)3-catalyzed formal dipolar [4π+2σ] cycloaddition of bicyclo[1.1.0]butanes with ...
Jian Zhang +4 more
semanticscholar +1 more source