679799-36-1Relevant academic research and scientific papers
Trialkylphosphine-Mediated Synthesis of 2-Acyl Furans from Ynenones
Xu, Chao,Wittmann, Stéphane,Gemander, Manuel,Ruohonen, Venla,Clark, J. Stephen
supporting information, p. 3556 - 3559 (2017/07/17)
A novel reaction for the synthesis of 2-acyl furans is reported. The reaction is believed to proceed by sequential addition of a trialkylphosphine to an ynenone, 5-exo-dig cyclization to form the furan, and oxidation of the resulting phosphonium ylide with molecular oxygen. Many common functional groups are tolerated during the reaction, and the products are obtained in good to excellent yield under the mild conditions. This methodology offers efficient access to biologically important compounds, including fused polycyclic compounds and furaldehydes, from simple starting materials.
Stereoselective synthesis of enynones via base-catalyzed isomerization of 1,5-disubstituted-2,4-pentadiynyl silyl ethers or their alcohol derivatives
Chen, Jingjin,Fan, Guoqin,Liu, Yuanhong
supporting information; experimental part, p. 4806 - 4810 (2010/12/19)
1,5-Disubstituted-2,4-pentadiynyl silyl ethers undergo smooth desilylative isomerization to afford cis-enynones as major products with moderate stereoselectivities in the presence of a catalytic amount of KOtBu or DBU. While the isomerization reactions of their alcohol derivatives catalyzed by KOH, KOtBu or NaH take place efficiently to produce trans-enynones with high stereoselectivities. These reactions provide convenient and practical routes for the synthesis of enynones with a wide range of substitution groups.
A convenient method for the preparation of α-vinylfurans by phosphine-initiated reactions of various substituted enynes bearing a carbonyl group with aldehydes
Kuroda, Hirofumi,Hanaki, Emi,Izawa, Hironori,Kano, Michiko,Itahashi, Hiromi
, p. 1913 - 1920 (2007/10/03)
α-Vinylfurans were obtained by phosphine-initiated cyclization of various enynes bearing a carbonyl group 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 of the carbonyl group (R3).
Regio- and stereoselective synthesis of vinylallenes by 1,5-(S(N)'')- substitution of enyne acetates and oxiranes with organocuprates
Purpura, Martin,Krause, Norbert
, p. 267 - 275 (2007/10/03)
Enyne acetates 2, 4, 6, and 8, as well as enyne oxiranes 10, with different substitution patterns react with organocuprates regioselectively under 1,5-(S(N)2'')-substitution to provide vinylallenes 11 and 12. With lithium dimethylcuprate, reduced vinylallenes originating from a [formal) transfer of a hydride ion to the substrate are formed in some cases. The products are usually obtained as mixtures of (E/Z)-isomers; however, pure (E)-vinylallenes are formed occasionally. The 1,5-substitutions can also be carried out with catalytic amounts of copper reagents. The reaction of chiral enyne acetate (S)-2a with tBu2CuLi · LiCN proceeds enantioselectively, so that this transformation constitutes a new case of remote stereocontrol.
