Ruthenium-Catalyzed [2+2+2] Cycloaddition of 1,6-Enynes and Unactivated Alkynes: Access to Ring-Fused Cyclohexadienes
作者:Rui Liu、Laurent Giordano、Alphonse Tenaglia
DOI:10.1002/asia.201700642
日期:2017.9.5
The [2+2+2] intermolecular carbocyclization reactions between 1,6‐enynes and alkynes catalyzed by [RuCl(cod)(Cp*)] (cod=1,5‐cyclooctadiene, Cp*=pentamethylcyclopentadienyl) are reported to provide bicyclohexa‐1,3‐dienes. The presented reaction conditions are compatible with internal and terminal alkynes and the chemo‐ and regioselectivity issues are controlled by the presence of substituents at the
A sequential Rh(i)-catalyzed vinylation/[2 + 1]carbocyclization between enynes and diazo compounds has been developed. This transformation features a wide range of enynes and acceptor/acceptor diazo compounds, providing easy access to versatile vinyl-substituted azabicyclo[3.1.0]hexanes having a broad tolerance to functional groups.
A Sequential Route to Cyclopentenes from 1,6-Enynes and Diazo Ketones through Gold and Rhodium Catalysis
作者:Balaji S. Kale、Hsin-Fu Lee、Rai-Shung Liu
DOI:10.1002/adsc.201600980
日期:2017.2.2
aryl diazo ketones through two new reaction sequences involving initial gold‐catalyzedcyclization of 1,6‐enynes with diazo species, followed by rhodium‐catalyzed skeletal rearrangement of the resulting 3‐cyclopropyl‐2‐en‐1‐ones. In most instances the rhodium‐catalyzed reactions afforded cyclopentene derivatives whereas several n‐alkyl‐ or ortho‐substituted phenyl ketones delivered seven‐membered oxacycles
A cascade of styrylynols promoted by MnO2 allows the synthesis of fused tricycles with a naphthalene core. The reaction occurs under ambient conditions, offering a practical synthetic tool because of the inexpensive and abundant manganese species. The method affords products through the sequential oxidation of a propargyl alcohol, stepwise Diels–Alder cyclization, and finally rearomatization. According
Rhodium-Catalyzed [5+2] Cycloaddition of 3-Acyloxy-1,4-enyne with Alkene or Allene
作者:Wangze Song、John C. Lynch、Xing-zhong Shu、Weiping Tang
DOI:10.1002/adsc.201600196
日期:2016.6.16
type of Rh‐catalyzed [5+2] cycloaddition by using 3‐acyloxy‐1,4‐enyne (ACE) as the 5‐carbon building block. In this update, we show that ACE can undergo intramolecular [5+2] cycloaddition with either an alkene or an allene in the presence of an appropriate rhodium catalyst and ligands to afford bicyclic compounds with multiple stereogenic centers. In most cases, cis‐fused bicyclo[5.3.0]decadienes are