cycloaddition reaction by merging organic photoredox and Lewisacid catalysis, providing a straightforward and efficient approach for directly installing a benzofuran skeleton on the saturated aza-heterocycles. In this protocol, we also describe a novel organic photocatalyst (t-Bu-DCQ) with the advantages of a wider redox potential, easy synthesis, and a low price. Furthermore, the stepwise activation mechanism
在此,我们报告了通过合并有机光氧化还原和路易斯酸催化的光诱导脱氢/(3+2) 环加成反应,为在饱和氮杂杂环上直接安装苯并呋喃骨架提供了一种简单有效的方法。在该协议中,我们还描述了一种新型有机光催化剂 ( t -Bu-DCQ),其具有更广泛的氧化还原电位、易于合成和价格低廉的优点。此外,一系列实验和计算研究证明了双 C(sp 3 )-H 键的逐步激活机制。
Diamine novel acid dianhydride and novel polyimide composition formed therefrom
申请人:Kaneka Corporation
公开号:US07019104B1
公开(公告)日:2006-03-28
An object of present invention is to provide a diamine and an acid dianhydride having photoreactivity and thermoreactivity and a polyimide composition containing the diamine and the acid dianhydride as monomer components, and specifically to synthesize a diamine and an acid dianhydride having a photoreactive and thermoreactive group containing a double bond or triple bond such as cinnamic acid, chalcone, benzalacetophenone, stilbene, coumarin, pyrone, allyl, propargyl, and acetylene or a derivative skeleton thereof so as to exhibit photoreactivity and thermoreactivity specific to the reactive group, thereby providing a polyimide composition containing the diamine and the acid dianhydride.
Herein, we describe an unprecedented (3 + 3) cycloadditionreaction of the donor–acceptorcyclopropanes with quinone esters toward the construction of chroman scaffolds in moderate to good yields. Interestingly, the strategy is also adjustable toward a (3 + 2) cycloaddition by just switching the Lewis acid to furnish benzofuran scaffolds. Based on the choice of Lewis acid used, the same set of precursors
Sc(III)-catalyzed domino C–C and C–N bond formation of N-sulfonyl aziridines with quinones has been accomplished to furnish functionalized indolines at a moderate temperature. The umpolung reactivity of aziridines, radical pathway, mild reaction conditions, substrate scope, and coupling of drug molecules in a postsynthetic application are the important practical features.
Asymmetric Synthesis of Axially Chiral Arylpyrazole via an Organocatalytic Arylation Reaction
作者:Xi Gao、Chengwen Li、Li Chen、Xin Li
DOI:10.1021/acs.orglett.3c02694
日期:2023.10.27
enantioselective arylationreaction of 3-aryl-5-aminopyrazoles and quinone derivatives was realized using a chiral phosphoric acid catalyst under mild conditions. The reaction has a broad scope with respect to both arylationreaction partners and hence offers rapid access to an array of axially chiral arylpyrazoles with pretty outcomes (up to 95% yield and 99% ee). Notably, the reaction is very efficient