Synthesis of 1,5-disubstituted (E)-pent-2-en-4-yn-1-ones
摘要:
The condensation of 3-arylpropynals with aryl methyl ketones in the presence of sodium hydroxide in 50% aqueous ethanol at 0A degrees C (Claisen-Schmidt reaction) afforded up to 89% of the corresponding (E)-1,5-diarylpent-2-en-4-yn-1-ones. The E configuration of the double C=C bond and cis conformation of the enone fragment in the products in crystal and CDCl3 solution were determined by X-ray analysis and H-1 NMR spectroscopy.
Synthesis and Cytotoxicity of Selenium-Containing Dienones
作者:D. M. Gusev、A. S. Bunev、A. A. Golovanov
DOI:10.1134/s1070363220020085
日期:2020.2
occurs regioselectively at the β-carbon of the triple bond of 1,5-disubstituted pent-2-ene-4-yne-1-ones, pent-4-ene-2-yne-1-ones and pent-1-ene-4-yne-3-ones. The resulting selenium-containing conjugateddienones exhibit pronounced cytotoxicity against some tumor cell lines.
Applications of Thermal Activation, Ball-milling and Aqueous Medium in Stereoselective Michael Addition of Nitromethane to Enynones Catalyzed by Chiral Squaramides
作者:Żaneta A. Ignatiuk、Mikołaj J. Janicki、Robert W. Góra、Krzysztof Konieczny、Rafał Kowalczyk
DOI:10.1002/adsc.201801498
日期:2019.3.5
to conjugated en‐ynones was performed through the application of chiral squaramides. Three non‐classical approaches to promote the addition reaction were tested, including activation of the nucleophile by inorganic base in a biphasic aqueous system, thermal activation, and ball‐milling. Hydrogen‐bonding catalysis was effective in all these methods, providing 1,4‐addition products in high yields and
A convenient method for the preparation of α-vinylfurans by phosphine-initiated reactions of various substituted enynes bearing a carbonyl group with aldehydes
at the ene end in the presence of various aldehydes, in moderate to high yields. The reaction may consist of 1,6-addition of phosphine to the enynes, ring closure, and Wittig reaction between the ylid resulting from cyclization and an aldehyde. Thus, various aldehydes were able to be used in the reaction. The reaction was influenced greatly by the substituents at the acetylene position (R1) and the α-position
Multicomponent reaction of conjugated enynones with malononitrile and sodium alkoxides: Complex reaction mechanism of the formation of pyridine derivatives
作者:Anastasiya V. Kuznetcova、Ivan S. Odin、Alexander A. Golovanov、Iakov M. Grigorev、Aleksander V. Vasilyev
DOI:10.1016/j.tet.2019.06.041
日期:2019.8
Reaction of conjugated enynones,1,5-diarylpent-2-en-4-yn-1-ones, with malononitrile and sodium alkoxides in the corresponding alcohols at room temperature for 3–23 h results in the formation of two types of compounds (E)-/(Z)-6-aryl-4-(2-arylethenyl)-2-alkoxypyridine-3-carbonitriles (substituted nicotinonitriles), as the major reaction products in yields up to ca. 40–80%, and 6-aryl-4-arylethynyl-2-alkoxypyridines
Enantioselective Synthesis of α-Chiral Propargylic Silanes by Copper-Catalyzed 1,4-Selective Addition of Silicon Nucleophiles to Enyne-Type α,β,γ,δ-Unsaturated Acceptors
作者:Wenbin Mao、Martin Oestreich
DOI:10.1021/acs.orglett.0c03046
日期:2020.10.16
A copper-catalyzed deconjugative addition of silicon nucleophiles to a broad range of enyne-type α,β,γ,δ-unsaturated acceptors with high enantiocontrol is reported. The method is 1,4-selective with hardly any formation of the 1,6-adduct. The double-bond geometry is shown to be critical for achieving this chemoselectivity: exclusive 1,4-addition for E and predominant 1,6-addition for Z. By this, E-configured