A General and Regioselective Synthesis of Cyclopentenone Derivatives through Nickel(0)-Mediated [3 + 2] Cyclization of Alkenyl Fischer Carbene Complexes and Internal Alkynes
作者:José Barluenga、Pablo Barrio、Lorena Riesgo、Luis. A. López、Miguel Tomás
DOI:10.1021/ja075106+
日期:2007.11.1
2-cyclopentenone derivatives 3-6 are synthesized by the nickel(0)-mediated [3 + 2] cyclizationreaction of chromium alkenyl(methoxy)carbenecomplexes1 and internal alkynes2. The reaction takes place with complete regioselectivity with both unactivated alkynes and activated alkynes (electron-withdrawing and electron-donating substituted alkynes). Representative cycloadducts containing boron and tin
The imino‐Nazarov cyclization of the polysubstituted pentan‐1,4‐diene‐3‐imines was realized. To this aim, a one‐pot procedure involving reductive alkenyliminylation of α,β‐unsaturated secondary amides with potassium organotrifluoroborates, followed by acid‐catalyzed imino‐Nazarov cyclization of the polysubstituted pentan‐1,4‐diene‐3‐imine intermediates, was studied systematically. This mild, operationally
Brønsted Acid-Mediated Nazarov Cyclization of Vinylallenes
作者:Yen-Ku Wu、F. G. West
DOI:10.1021/jo101112t
日期:2010.8.6
Treatment of siloxy enynes with base leads to the corresponding vinylsiloxyallenes which undergo Nazarov cyclization in the presence of trifluoroacetic acid to provide the cyclized product as a mixture of regioisomers in moderate to good overall yield.
Nickel(0)-Catalyzed Enantioselective Annulations of Alkynes and Arylenoates Enabled by a Chiral NHC Ligand: Efficient Access to Cyclopentenones
作者:Joachim S. E. Ahlin、Pavel A. Donets、Nicolai Cramer
DOI:10.1002/anie.201408364
日期:2014.11.24
nickel‐catalyzed reductive [3+2] cycloaddition of α,β‐unsaturated aromatic esters and alkynes constitutes an efficient method for their synthesis. Here, nickel(0) catalysts comprising a chiral bulky C1‐symmetric N‐heterocyclic carbene ligand were shown to enable an efficient asymmetric synthesis of cyclopentenones from mesityl enoates and internal alkynes under mild conditions. The bulky NHC ligand
Acid-Promoted Iso-Nazarov Cyclization of Conjugated <i>trans</i>-Dienones and Dienals for the Synthesis of 2-Cyclopentenones
作者:Agustina La-Venia、Lucas Passaglia、Lucía Gurgone、Vincent Gandon、Martín J. Riveira
DOI:10.1021/acs.joc.2c01783
日期:2022.10.21
The acid-promoted cyclization of all-trans linearly conjugated dienones and dienals constitutes a synthetic strategy for the construction of 2-cyclopentenones.