Enantioselective Multicomponent Synthesis of Fused 6-5 Bicyclic 2-Butenolides by a Cascade Heterobicyclisation Process
作者:Marcos G. Suero、Raquel De la Campa、Laura Torre-Fernández、Santiago García-Granda、Josefa Flórez
DOI:10.1002/chem.201102288
日期:2012.6.4
heterobicyclisation products is the result of the regioselective integration of the Grignardreagent as a propargyl fragment followed by a cascade CO/alkyne/CO insertion, ketene trapping and elimination sequence. By using lithium enolates of chiral N‐acetyl‐2‐oxazolidinones and the corresponding propargylic organocerium reagents, both enantiomers of these bicyclic heterocycles were efficiently prepared with
Water Freezing as a Regiocontrol Element in the Multicomponent Assembly of Cyclic Enones
作者:Raquel De la Campa、Josefa Flórez
DOI:10.1002/chem.201404670
日期:2015.1.26
Regioselective synthesis of dialkoxy 2‐cyclopentenones and 2‐cyclohexenones with novel substitution patterns has been accomplished by the one‐pot combination of three simple starting materials (chromium carbene complex, Weinreb acetamide lithium enolate and 1‐alkoxyallenyllithium) under either anhydrous conditions or water‐promoted solidification of the reaction mixture. These results revealed an unprecedented
Diastereoselective Multicomponent Cyclizations of Fischer Carbene Complexes, Lithium Enolates, and Allylmagnesium Bromide Leading to Highly Substituted Five- and Six-Membered Carbocycles
作者:José Barluenga、Iván Pérez-Sánchez、Marcos G. Suero、Eduardo Rubio、Josefa Flórez
DOI:10.1002/chem.200600491
日期:2006.9.18
The one-pot sequential reaction of a chromium alkoxycarbene complex, a ketone or ester lithiumenolate, and allylmagnesiumbromide enabled the selective synthesis of novel diastereomerically pure pentasubstituted cyclopentanols or tetrasubstituted 1,4-cyclohexanediols, depending on the degree of substitution at the Cbeta position of the enolate anion. A few exceptions have been encountered in which tetrasubstituted
Enantioselective Synthesis of 4-Hydroxy-2-cyclohexenones through a Multicomponent Cyclization
作者:José Barluenga、Marcos G. Suero、Raquel De la Campa、Josefa Flórez
DOI:10.1002/anie.201004413
日期:2010.12.10
and a propargylic organomagnesium reagent giving access to novel and densely functionalized 4‐allenyl‐2‐cyclohexenones (see scheme). These useful synthetic intermediates have been prepared through a cyclization process that involves newly reported reaction steps and an unusually high level of asymmetric induction.
Palladium-Catalyzed Reductive Cross-Coupling Reaction of Aryl Chromium(0) Fischer Carbene Complexes with Aryl Iodides
作者:Kang Wang、Yu Lu、Fangdong Hu、Jinghui Yang、Yan Zhang、Zhi-Xiang Wang、Jianbo Wang
DOI:10.1021/acs.organomet.7b00657
日期:2018.1.8
The first palladium-catalyzed reductive cross-couplings of aryl chromium(0) carbene complexes with aryliodides have been realized. This coupling reaction shows excellent functional group tolerance and high efficiency. Mechanistically, aryl chromium(0) carbene complexes undergo transmetalation with arylpalladium species to generate palladium(II) carbene intermediates, which is followed by migratory