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
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.
Pd-Catalyzed Inter- and Intramolecular Carbene Transfer from Group 6 Metal−Carbene Complexes<sup>1</sup>
作者:Miguel A. Sierra、Juan C. del Amo、María J. Mancheño、Mar Gómez-Gallego
DOI:10.1021/ja002497i
日期:2001.2.1
intramolecular carbene transfer reactions has been studied. Thus, pentacarbonyl[(aryl)(methoxy)carbene]chromium(0) and tungsten complexes, 10, efficiently dimerize at room temperature in the presence of diverse Pd(0) and Pd(II)/Et(3)N catalysts. The effect of additives (PPh(3), AsPh(3), or SbPh(3)) on the nature and the isomeric ratio of the reaction products is negligible. The nature of the reaction products