A Divergent and Selective Synthesis of Isomeric Benzoxazoles from a Single N–Cl Imine
作者:Cheng-yi Chen、Teresa Andreani、Hongmei Li
DOI:10.1021/ol202844c
日期:2011.12.2
divergent and regioselective synthesis of either 3-substituted benzisoxazoles or 2-substituted benzoxazoles from readily accessible ortho-hydroxyaryl N–H ketimines is described. The reaction proceeds in two distinct pathways through a common N–Cl imine intermediate: (a) N–O bond formation to form benzisoxazole under anhydrous conditions and (b) NaOCl mediated Beckmann-type rearrangement to form benzoxazole
was found to act as an efficient oxidant to trigger the [1,2]-arylmigration towards the formation of the desired heterocycles. Depending on the substitution pattern, the results revealed another mechanistic pathway through which benzisoxazoles or 1H-indazoles could be formed. The Beckmann-type rearrangement strategy was applied to the synthesis of benzimidazole-containing biorelevant targets such as
An improved synthesis of 1,2-benzisoxazoles: TBAF mediated 1,3-dipolar cycloaddition of nitrile oxides and benzyne
作者:Christian Spiteri、Pallavi Sharma、Fengzhi Zhang、Simon J. F. Macdonald、Steve Keeling、John E. Moses
DOI:10.1039/b922489k
日期:——
An efficient synthesis of a range of 1,2-benzisoxazoles using an improved1,3-dipolarcycloaddition of nitrileoxides and benzyne is described. Key to the procedure is the in situgeneration of the reactive nitrileoxide and benzyne reaction partners mediated by TBAF. Reactions are complete within 30 s, giving the target products in good to excellent yield.
An efficient entry to 1,2-benzisoxazoles via 1,3-dipolar cycloaddition of in situ generated nitrile oxides and benzyne
作者:Christian Spiteri、Christopher Mason、Fengzhi Zhang、Dougal J. Ritson、Pallavi Sharma、Steve Keeling、John E. Moses
DOI:10.1039/b927235f
日期:——
An efficient protocol for the synthesis of a range of 1,2-benzisoxazoles using an improved1,3-dipolarcycloaddition of nitrileoxides and benzyne is described. Key to the procedure is the in situgeneration of the reactive nitrileoxide and benzyne reactants simultaneously.
IRIDIUM COMPLEX AND ORGANIC ELECTROLUMINESCENCE DEVICE USING THE SAME
申请人:YEN FENG-WEN
公开号:US20200157129A1
公开(公告)日:2020-05-21
The present invention discloses an iridium complex represented by the following formula (1) and an organic electroluminescence device using the iridium complex as a phosphorescent dopant material. The phosphorescent dopant material may lower a driving voltage and power consumption and increase a current efficiency and half-life of the organic electroluminescence device.
The same definition as described in the present invention.