CuBr-Catalyzed Coupling of <i>N-</i>Tosylhydrazones and Terminal Alkynes: Synthesis of Benzofurans and Indoles
作者:Lei Zhou、Yi Shi、Qing Xiao、Yizhou Liu、Fei Ye、Yan Zhang、Jianbo Wang
DOI:10.1021/ol103009n
日期:2011.3.4
A new method for the synthesis of benzofurans or indoles via ligand-free CuBr-catalyzed coupling/cyclization of terminalalkynes with N-tosylhydrazones derived from o-hydroxy- or o-aminobenzaldehydes has been developed. A wide range of functional groups were found that are able to tolerate the reaction conditions.
Direct Synthesis of 2-Methylbenzofurans from Calcium Carbide and Salicylaldehyde <i>p</i>-Tosylhydrazones
作者:Rugang Fu、Zheng Li
DOI:10.1021/acs.orglett.8b00676
日期:2018.4.20
A new methodology for the construction of methyl-substituted benzofuran rings from the reactions of calcium carbide with salicylaldehyde p-tosylhydrazones/2-hydroxyacetophenone p-tosylhydrazones is described. Various 2-methylbenzofurans and 2,3-dimethylbenzofurans could be obtained in satisfactory yield by using a cuprous chloride catalyst. The advantages of this protocol include the use of a readily
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