A most user-friendly protocol for ring closing metathesis reactions
作者:Alois Fürstner、Lutz Ackermann
DOI:10.1039/a808810a
日期:——
Ring closing metathesis reactions (RCM) can be conveniently achieved in a photo-assisted manner simply by heating a solution of the diene substrate, catalytic amounts of commercially available [(p-cymene)RuCl2]2 4 and PCy3 in CH2Cl2 under neon light.
We describe surface-modified sintered polyethylene sheets as a suitable carrier system for various catalysts. The material shows high rigidity and no swelling properties and allows for easy removal and reuse of the supported catalysts. The application was demonstrated for Pd-, Rh-, and Ru-catalysts in Suzuki couplings, hydroformylation, and olefin metathesis, respectively.
Ruthenium carbene complexes with imidazolin-2-ylidene ligands allow the formation of tetrasubstituted cycloalkenes by RCM
作者:Lutz Ackermann、Alois Fürstner、Thomas Weskamp、Florian J. Kohl、Wolfgang A. Herrmann
DOI:10.1016/s0040-4039(99)00919-3
日期:1999.6
Chemically quite robust ruthenium carbene complexes 2–8 bearing one or two imidazolin-2-ylidene ligands are highlyactivecatalysts for all types of ring closing metathesis reactions (RCM). Importantly, they even allow the formation of tetrasubstituted alkenes that were previously out of reach of ruthenium-basedmetathesiscatalysts.
Indenylidene Complexes of Ruthenium: Optimized Synthesis, Structure Elucidation, and Performance as Catalysts for Olefin Metathesis—Application to the Synthesis of the ADE-Ring System of Nakadomarin A
complex 3 is as good as or even superior to the classical Grubbs carbene 1 in terms of yield, reaction rate, and tolerance towards polar functional groups. Complex 3 turns out to be the catalyst of choice for the synthesis of the enantiopure core segment 77 of the marine alkaloid nakadomarin A 60 comprising the ADE rings of this target. Together with a series of other examples, this particular application
Cationic ruthenium allenylidene complexes as a new class of performing catalysts for ring closing metathesis
作者:A. Fürstner、A. Fürstner、M. Picquet、C. Bruneau、P. H. Dixneuf
DOI:10.1039/a803286f
日期:——
Cationic allenylidene ruthenium complexes [Ru CCCR2(L)(Cl)(arene)]PF6 (L = PCy3, PPri3), easily prepared from RuCl2(L)(p-cymene), prop-2-yn-1-ol and NaPF6, are found to be excellent catalyst precursors for ring closing olefin metathesis.