Gold-Catalyzed Oxidative Cyclizations of {<i>o</i>-(Alkynyl)phenyl propargyl} Silyl Ether Derivatives Involving 1,2-Enynyl Migration: Synthesis of Functionalized 1<i>H</i>-Isochromenes and 2<i>H</i>-Pyrans
作者:Jidong Zhao、Wei Xu、Xin Xie、Ning Sun、Xiangdong Li、Yuanhong Liu
DOI:10.1021/acs.orglett.8b02380
日期:2018.9.7
A new and convenient strategy for the synthesis of functionalized 1H-isochromene and 2H-pyran derivatives based on gold-catalyzed oxidative cyclizations of o-(alkynyl)phenyl propargyl ether derivatives has been developed. The reaction proceeds via gold-catalyzed highly regioselective oxidation, followed by 1,2-migration of an enynyl group and nucleophlic addition. Isocoumarins were also constructed
Gold-catalyzed cyclo-isomerization of 1,6-diyne-4-en-3-ols to form naphthyl ketone derivatives
作者:Jian-Jou Lian、Rai-Shung Liu
DOI:10.1039/b618291g
日期:——
We report a new efficient gold-catalyzed cyclization of 1,6-diyne-4-en-3-ols to give naphthylketone derivatives under ambient conditions. The value of this cyclization is reflected by its applicability to a wide range of alcohol substrates.
Gold-Catalyzed Cyclization of 1,6-Diyne-4-en-3-ols: Stannyl Transfer from 2-Tributylstannylfuran Through Au/Sn Transmetalation
作者:Yifeng Chen、Ming Chen、Yuanhong Liu
DOI:10.1002/anie.201201523
日期:2012.6.18
Gold‐tinted: A gold catalyzed cyclization reaction of 1,6‐diyne‐4‐en‐3‐ols, incorporating an in situ stannyltransfer reaction involving 2‐tributylstannylfuran, gives synthetically valuable 2‐stannylnaphthalenes (see scheme; DCE=dichloroethane). A gem‐diaurated furan complex, was isolated and fully characterized by X‐ray crystallographic analysis, and provides strong evidence for a tin to gold transmetalation
and practical route for the preparation of highly substituted fluorenones and analogues via solvent-free ruthenium trichloride mediated [2 + 2 + 2] cycloaddition of α,ω-diynes and alkynes has been developed. This green chemistry approach involves a solventless and atom-economical catalytic process to generate densely functionalized fluorenones and related derivatives of high synthetic utility.
Fluoro-Ene Reaction Versus [2+2] Cycloaddition in the Thermal C<sup>2</sup>-C<sup>6</sup>Cyclization of Enyne-Allenes: An Experimental and Theoretical Investigation
作者:M. Emin Cinar、Chandrasekhar Vavilala、Ralph Jaquet、Jan W. Bats、Michael Schmittel
DOI:10.1002/ejoc.201402438
日期:2014.8
A series of fluoroalkyl-substituted enyne-allenes have been synthesized by a new route with the aim of elucidating the possibility of a fluoro-ene reaction via an intermediate fulvenyl diradical generated in the thermal C2–C6 (Schmittel) cyclizationreaction. As a result of the strong C–F bond, fluorine atom transfer was not observed. Instead, 1H-cyclobuta[a]indenes were formed in good yields despite