Results 11 to 20 of about 337 (160)
Advanced Synthesis &Catalysis, Volume 366, Issue 24, Page 5008-5014, December 17, 2024.Abstract In this work, we present an organocatalytic spiroannulation method that provides access to spirocyclic benzofuran‐2‐ones. The reaction proceeds via the generation of an azolium dienolate from an α‐bromo‐α,β‐unsaturated aldehyde using a chiral N‐heterocyclic carbene, followed by annulation with benzofuran‐2‐one‐derived alkenes.
Ladislav Lóška +8 more
wiley +2 more sources
A C1-symmetric N-heterocyclic carbene catalysed oxidative spiroannulation of isatin-derived enals: highly enantioselective synthesis of spirooxindole δ-lactones. [PDF]
RSC Adv, 2018 A NHC-catalysed spiroannulation of isatin-derived enals and 1,3-dicarbonyl compounds has been developed, enabling enantioselective synthesis of synthetically important spirooxindole δ-lactones.
Lin JB +5 more
europepmc +2 more sources
European Journal of Organic Chemistry, Volume 2022, Issue 25, July 7, 2022., 2022 Easily accessible isoxazol‐5(4H)‐ones are useful precursors of different heterocycles. In this work, the ruthenium‐catalyzed transformation of 4‐alkenyl‐substituted isoxazol‐5‐ones to 1H‐pyrrole derivatives is reported. Abstract Easily accessible isoxazol‐5(4H)‐ones are useful precursors of heterocycles.
Letizia Molteni +6 more
wiley +1 more source
Synthesis of N-(2,8-Dioxo-1-oxaspiro[4.5]deca-6,9-dien-7-yl) Acetamide and Benzamide
Molbank, 2009 The syntheses of two new spirolactones are described. Each compound was obtained as an off-white solid in 66% yields from 4-hydroxy-3-nitrobenzaldehyde.
Guy L. Plourde, Randy R. Spaetzel
doaj +1 more source
Molecules, 2008 The novel 3H-spiro[1-benzofuran-2-cyclopentan]-3-one skeleton has been madeaccessible by different routes. One- and two-step protocols lead to tricyclic and tetracyclicbenzofuranones 2 and 3, respectively.
Gunter Fischer +4 more
doaj +1 more source
Diastereoselective spiroannulation of phenolic derivatives: Effect of steric hindrance on the diastereoselectivity. [PDF]
, 2017 The objective of this study was to determine the effect, if any, that steric factors have on the oxidative spiroannulation of simple phenols bearing substituents that are increasing in size.
openaire +3 more sources
Reductive Spiroannulation of Nitriles with Secondary Electrophiles
, 2016 The scope of reductive decyanation and spiroannulation reactions has been expanded to include secondary electrophiles for potentially useful transformations.
Matthew D. Morin (2096020) +1 more
core +2 more sources
Synthesis of 6-Methoxy-1-oxaspiro[4,5]deca-6,9-diene-8-one
Molecules, 2002 The synthesis of a new spirolactone is described. The title compound is obtained as a white solid in 46% yield from 3-(4-hydroxy-2-methoxyphenyl)propanoic acid using [Bis(trifluoroacetoxy)iodo]benzene (PIFA) as the oxidant.
Benjamin B. Fisher, Guy L. Plourde
doaj +1 more source
, 2022 The palladium-catalyzed divergent asymmetric synthesis of chiral spiro-furanindoline derivatives is described. The zwitterionic alkoxy π-allyl Pd(II) intermediate, generated catalytically from vinyl ethylene carbonate (VEC), could undergo ligand ...
Su Min Park (14248329) +3 more
core +1 more source
I2–PPh3 mediated spiroannulation of unsaturated b-dicarbonyl compounds. The first synthesis of (±)-negundoin A [PDF]
, 2013 An efficient and stereoselective spiroannulation of unsaturated enols is reported. Unsaturated b-dicarbonyl compounds undergo cyclization by reaction with catalytic I2–PPh3, affording the corresponding spiro enol ether derivatives, with complete regio ...
Chahboun, Rachid +6 more
core +1 more source