我们提出了可持续的,直观的,高度区域选择性的,可见光驱动的铜催化的N-甲苯磺酰with与末端炔烃的有氧氧化级联环化反应,以在室温下制备3-芳基香豆素。这种操作简单的方法已成功应用于各种N-甲苯磺酰hydr和炔烃(49个实例),并且进展顺利,可提供具有生物活性的化合物,例如单胺氧化酶B(MAO-B)抑制剂和辣根过氧化物酶(HRP)抑制剂,在温和的条件下具有令人满意的产量。此外,机理研究表明,反应是通过铜进行的(II18 O 2同位素标记实验证明)-超氧或-过氧配合物介导的末端炔烃的氧化环化反应。
Palladium-catalyzed coupling of N-tosylhydrazones and β-bromostyrene derivatives: new approach to 2H-chromenes
作者:Yamu Xia、Ying Xia、Yan Zhang、Jianbo Wang
DOI:10.1039/c4ob01979b
日期:——
structural motif that exists in natural products and non-natural compounds possessing interesting biological activities. In this investigation, a highly efficient approach toward 2H-chromenes has been developed based on palladium-catalyzedcoupling of N-tosylhydrazones and β-bromostyrenes. The mechanism of this reaction is proposed that involves the formation of vinyl palladium by carbene migratory insertion
2 H -Chromene是存在于天然产物和具有有趣生物活性的非天然化合物中的重要结构基序。在这项研究中,基于钯催化的N-甲苯磺酰hydr和β-溴苯乙烯的偶联,已经开发出一种高效的2 H-苯甲基苯胺的方法。提出了该反应的机理,该机理涉及通过卡宾迁移插入和分子内亲核取代形成乙烯基钯。
Facile access to 2,2-diaryl 2<i>H</i>-chromenes through a palladium-catalyzed cascade reaction of <i>ortho</i>-vinyl bromobenzenes with <i>N</i>-tosylhydrazones
作者:Heng Zhang、Yinghua Yu、Xueliang Huang
DOI:10.1039/d0ob00978d
日期:——
A palladium-catalyzed cascade reaction of ortho-vinyl bromobenzenes with N-tosylhydrazones has been developed, which provides a facile approach to 2,2-disubstituted 2H-chromenes. The migration of palladium from the aryl to vinyl position is crucial, as the in situ produced vinyl palladium intermediate could further react with diazocompounds to generate the reactive species for the sequential annulation
CuI-Catalyzed Selective 3-Alkylation of Indoles with <i>N</i>
-Tosylhydrazones and the I<sub>2</sub>
-Mediated Further Cyclization to Chromeno[2,3-<i>b</i>
]Indoles
作者:Chun-Bao Miao、Yan-Fang Sun、He Wu、Xiao-Qiang Sun、Hai-Tao Yang
DOI:10.1002/adsc.201800206
日期:2018.7.4
The CuI‐catalyzed reaction of indoles with N‐tosylhydrazones derived from the ortho‐/para‐hydroxybenzaldhydes affords selectively the C‐3 alkylated products rather than the N‐alkylated products. In addition, the I2‐mediated cyclization of the generated C‐3 alkylated products allows the concise synthesis of chromeno[2,3‐b]indole derivatives.
吲哚与碘化亚铜催化反应Ñ -tosylhydrazones从派生邻- /对-hydroxybenzaldhydes得到选择性地将Ç -3烷基化产物,而不是Ñ烷基化产品。此外,生成的C-3烷基化产物的I 2介导的环化反应可简化chromeno [2,3- b ]吲哚衍生物的合成。
A copper(<scp>ii</scp>) perchlorate-promoted tandem reaction of internal alkynol and salicyl N-tosylhydrazone: direct access to isochromeno[3,4-b]chromene
作者:Hai Xiao Siyang、Xu Rui Wu、Xiao Yue Ji、Xin Yan Wu、Pei Nian Liu
DOI:10.1039/c4cc02862g
日期:——
A copper(ii) perchlorate-promoted tandem reaction of internal alkynol and salicyl N-tosylhydrazone provides a novel, concise method for constructing isochromeno[3,4-b]chromene in 35-94% yields. The tandem reaction involves cycloisomerization, formal [4+2] cycloaddition and an elimination process.
Palladium-Catalyzed Tandem Reaction of Alkyne-Based Aryl Iodides and Salicyl<i>N</i>-Tosylhydrazones to Construct the Spiro[benzofuran-3,2′-chromene] Skeleton
作者:Xue Song Shang、Nian Tai Li、Deng Yuan Li、Pei Nian Liu
DOI:10.1002/adsc.201501150
日期:2016.5.19
aryl iodides and salicyl N‐tosylhydrazones has been achieved to afford a series of compounds containing the novel spiro[benzofuran‐3,2′‐chromene] scaffold in moderate to good yields. This efficient catalytic reaction, which tolerates various functional groups, combines alkyne‐based 5‐exo‐dig cyclization, palladium(II) carbene migratory insertion and intramolecular cyclization, generating three new bonds