An efficient synthesis of 2,5-disubstitutedfurans directly from alkynyl ketones has been developed via tandem gold(I)-catalyzed isomerization of alkynyl ketones to allenyl ketones and cycloisomerization. The key to the success of this chemistry is the use of a biphenyl-2-ylphosphine ligand featuring a critical remote tertiary amino group.
Palladium‐Catalyzed Desulfitative Cross‐Coupling Reaction of Sodium Sulfinates with Propargylic Carbonates
作者:Anni Qin、Guirong Zhu、Qin Chen、Hui Qian、Shengming Ma
DOI:10.1002/adsc.201900698
日期:2019.10.22
Desulfitative cross‐coupling of propargylic carbonates with sodium sulfinates has been observed. The reaction exhibited good functional group compatibility affording allenes as a single product. Potential anticancer activities of these allene products were also studied.
Insertion of Isolated Alkynes into Carbon-Carbon σ-Bonds of Unstrained Cyclic β-Ketoesters via Transition-Metal-Free Tandem Reactions: Synthesis of Medium-Sized Ring Compounds
作者:Yuanyuan Zhou、Xianghua Tao、Qiyi Yao、Yulei Zhao、Yanzhong Li
DOI:10.1002/chem.201603798
日期:2016.12.12
transition‐metal‐free insertion of isolated alkynes into carbon–carbon σ‐bonds of unstrained cyclic β‐dicarbonyl compounds has been reported. These tandem reactions offer an efficient synthesis of medium‐sized ring or fused‐ring compounds through ring expansion. The methodology has the potential to be widely used throughout organic synthesis due to the easily accessible starting materials and mild reaction conditions
Ligand influence in the selective gold-mediated synthesis of allenes
作者:Pierrick Nun、Sylvain Gaillard、Alexandra M. Z. Slawin、Steven P. Nolan
DOI:10.1039/c0cc03071f
日期:——
The use of [(IPr)AuOH] permits the generation of gold(i)-amine complexes by a silver-freeprotocol. These in situ or well-defined complexes are used in a straightforward synthetic route to substituted allenes from propargylic acetates. The catalytic activity can be modulated as a function of the nature of the ligand bound to the gold-NHC moiety.
Vanadium(V)-mediated rearrangement/halogenation cascade: Synthesis of α-haloenones from propargyl alcohols
作者:Meng Zhao、Justin T. Mohr
DOI:10.1016/j.tet.2016.12.055
日期:2017.7
A method is described for the oxidative Meyer–Schuster-type rearrangement of propargylic alcohols to (Z)-α-chloro- and α-iodoenones using VOCl3 as a multifunctional reagent. The vanadium reagent is found to serve as rearrangement promoter as well as an active chlorenium ion donor. Yields are improved when VOCl3 is employed in conjunction with N-halosuccinimide reagents, giving some insights into the