65658-16-4Relevant articles and documents
Facile Access to Triazole-Fused 3,1-Benzoxazines Enabled by Metal-Free Base-Promoted Intramolecular C-O Coupling
Beletskaya, Irina P.,Kotovshchikov, Yury N.,Latyshev, Gennadij V.,Lukashev, Nikolay V.,Tatevosyan, Stepan S.
supporting information, (2021/10/21)
A convenient approach to assemble 1,2,3-triazole-fused 4 H -3,1-benzoxazines has been developed. Diverse alcohol-tethered 5-iodotriazoles, readily accessible by a modified protocol of Cu-catalyzed (3+2)-cycloaddition, were utilized as precursors of the target fused heterocycles. The intramolecular C-O coupling proceeded efficiently under base-mediated transition-metal-free conditions, furnishing cyclization products in yields up to 96%. Suppression of the competing reductive cleavage of the C-I bond was achieved by the use of Na 2CO 3in acetonitrile at 100 °C. This practical and cost-effective procedure features a broad substrate scope and valuable functional group tolerance.
Red phosphorescent compound and organic electroluminescent device using same
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Paragraph 0064-0066, (2020/01/03)
The invention discloses a red phosphorescent compound and an organic electroluminescent device using the same. In the organic electroluminescent device comprising an anode, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer and a cathode which are sequentially deposited, a phosphorescent compound as shown in a followingformula I can be used as a dopant of the light emitting layer, wherein R1, R2, R3, R4, R5 and R6 are independently selected from one of H, C1-C6 alkyls and C5-C8 cycloalkyls. The red phosphorescent material is high in efficiency, high in color purity and narrow in spectral effect.
Catalytic Synthesis of Indolines by Hydrogen Atom Transfer to Cobalt(III)–Carbene Radicals
Karns, Alexander S.,Goswami, Monalisa,de Bruin, Bas
supporting information, p. 5253 - 5258 (2017/12/15)
We report a new method for the synthesis of indolines from o-aminobenzylidine N-tosylhydrazones proceeding through a cobalt(III)–carbene radical intermediate. This methodology employs the use of inexpensive commercially available reagents and allows for the transformation of easily derivatized benzaldehyde-derived precursors to functionalized indoline products. This transformation takes advantage of the known propensity of radicals to undergo rapid intramolecular 1,5-hydrogen atom transfer (1,5-HAT) to form more stabilized radical intermediates. Computational investigations using density functional theory identify remarkably low barriers for 1,5-HAT and subsequent radical rebound displacement, providing support for the proposed mechanism. We explore the effect of a variety of nitrogen substituents, and highlight the importance of adequate resonance stabilization of radical intermediates to the success of the transformation. Furthermore, we evaluate the steric and electronic effects of substituents on the aniline ring. This transformation is the first reported example of the synthesis of nitrogen-containing heterocycles from cobalt(III)–carbene radical precursors.