Benign catalysis with zinc: atom-economical and divergent synthesis of nitrogen heterocycles by formal [3 + 2] annulation of isoxazoles with ynol ethers
作者:Xin-Qi Zhu、Han Yuan、Qing Sun、Bo Zhou、Xiao-Qin Han、Zhi-Xin Zhang、Xin Lu、Long-Wu Ye
DOI:10.1039/c8gc02051e
日期:——
zinc-catalyzed formal [3 + 2] annulation of isoxazoles with ynol ethers under exceptionally mild reaction conditions, leading to the atom-economical and divergent synthesis of 2-alkoxyl 1H-pyrroles and 3H-pyrroles, respectively. Importantly, this zinc-catalyzed protocol demonstrates the dramatically divergent reactivity from the relevant platinum catalysis, where the formal [4 + 2] annulation of isoxazoles with
Palladium-catalyzed haloallylation of aromatic ynol ethers with allyl chlorides: a highly regio- and stereoselective approach to (1E)-α-chloroenol ethers
Described herein is a Pd-catalyzed haloallylation of aromatic ynol ethers and allyl chlorides, allowing facile access to (1E)-α-chloroenol ethers in a highly regio- and stereoselective manner. The synthetic utility of this method is demonstrated well by the synthesis of the stereodefined multisubstituted enol ethers and α-allylated carbonyl compounds.
Ynol Ethers as Ketene Equivalents in Rhodium-Catalyzed Intermolecular [5 + 2] Cycloaddition Reactions
作者:Paul A. Wender、Christian Ebner、Brandon D. Fennell、Fuyuhiko Inagaki、Birte Schröder
DOI:10.1021/acs.orglett.7b02765
日期:2017.11.3
electron-rich alkynes (ynol ethers) have been found to provide a highly efficient, direct route to dioxygenated seven-membered rings, a common feature of numerous natural and non-natural targets and building blocks for synthesis. The reactions proceed in high yield at roomtemperature and tolerate a broad range of functionalities. Substituted VCPs were found to react with high regioselectivity.
Synthesis of (<i>E</i>)-α,β-Unsaturated Carbonyls<i>via</i>Silver-Catalyzed Tandem Epoxide Rearrangement/Intermolecular Carbonyl- Heteroalkyne Metathesis
stereoselective method for the synthesis of (E)‐α,β‐unsaturated carbonyls has been developed via a silver‐catalyzed tandem epoxide rearrangement/intermolecular carbonyl‐heteroalkyne metathesis. Various heteroalkynes including ynol ethers, ynamides, and thioalkynes work well for this transformation, leading to the production of (E)‐α,β‐unsaturatedesters, amides, and thioesters in moderate to excellent
Construction of 1-Naphthols via Benzannulation Based on the Reaction of Aryl <i>tert</i>-Butyl Ynol Ethers with Ynamides or Ynol Ethers
作者:Yihui Bai、Jing Yin、Zhicheng Liu、Gangguo Zhu
DOI:10.1021/acs.joc.5b01858
日期:2015.10.16
A new version of benzannulation featuring the use of aromatic tert-butyl ynol ethers as the convenient precursors for arylketenes has been developed. Both ynamides and ynol ethers undergo this reaction smoothly, giving 3-amino and 3-alkoxy 1-naphthols in good to excellent yields under the heated reaction conditions. The high efficiency, excellent regioselectivity, good functional group compatibility