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
Rapid access to benzo-annelated heterocycles, naphthalenes, and polysubstituted benzenes through a novel benzannulation reaction
作者:Inga Cikotiene、Rita Buksnaitiene、Rokas Sazinas
DOI:10.1016/j.tet.2010.11.073
日期:2011.1
mercaptoacetate triggered benzannulation reaction is described. The precursors are heterocyclic, aromatic or acyclic compounds bearing a carbonyl group at ortho position to an internal alkyne. The methodology does not require transition-metal catalysts and moreover it is general for the preparation of wide range of benzo-annelated heterocycles, naphthalenes and benzenes.
Synthesis of novel ferrocenated enynes via the Sonogashira coupling of ferrocenated vinyllic chlorides and alkyne in the catalytic presence of selenated NHC-Pd(II) full pincer complex under Cu and amine free aerobic conditions
作者:Vijesh Tomar、Charu Sharma、Meena Nemiwal、Raj K. Joshi
DOI:10.1016/j.jorganchem.2021.122095
日期:2021.12
established for the synthesis of novel ferrocenated enynes at feasible reaction condition. 0.002 mol % of the selenated NHC-Pd(II) pincer complex was found to be highly efficient to couple various substituted acetylenes with β-chloro-cinnamaldehyde/acrylonitriles/malononitrile in just 5 h under the areobic conditions. A library of 26 new ferrocene substituted enyne derivatives has been developed through
Gold(<scp>i</scp>) catalysed sequential dehydrative cyclisation/intermolecular [4 + 2] cycloaddition of alkynyldienols onto activated alkynes/alkenes: a facile route to substituted norbornadienes/norbornenes
作者:Anasuyamma Uruvakili、G. Gangadhararao、K. C. Kumara Swamy
DOI:10.1039/c5ob01458a
日期:——
cyclisation of alkynyldienols, followed by intermolecular [4 + 2] cycloaddition of in situ generated cyclopentadiene and activated alkynes/alkenes is described. The precursors, alkynyldienols, are obtained via sequential Sonogashira cross-coupling of 3-bromoenals, alkyne addition and reduction. Yields of the enynals and multisubstituted norbornadienes in all the cases are good to excellent.
Synthesis of functionalized unsymmetrical 1,3-butadiene-3-yne derivatives from β-halo styrene derivatives and their application in the synthesis of trisubstituted pyridines
作者:Vijayalakshmi Bandi、Veerababurao Kavala、Che-Hao Hsu、Ashok Konala、Bharath Kumar Villuri、Trimurtulu Kotipalli、Chun-Wei Kuo、Ching-Fa Yao
DOI:10.1039/c7ra07128k
日期:——
approach for the synthesis of functionalized unsymmetrical 1,3-butadiene-3-yne derivatives is reported starting from β-halo styrene and phenyl acetylene derivatives in the presence of PdCl2 and CuI catalysts. Functional groups such as aldehyde, cyano and ester groups are well tolerated and afford the desired functionalized dienynes. Further, these 1,3-buta-diene-3-yne derivatives are utilized for the