Cobalt-Catalyzed Addition of Arylzinc Reagents to Norbornene Derivatives through 1,4-Cobalt Migration
作者:Boon-Hong Tan、Naohiko Yoshikai
DOI:10.1021/ol501449j
日期:2014.6.20
A cobalt–diphosphine catalyst promotes the addition of an arylzinc reagent to a norbornene derivative to afford o-(2-exo-norbornyl)arylzinc species. This “migratory arylzincation” reaction is considered to involve insertion of norbornene into an arylcobalt species, alkyl-to-aryl 1,4-cobalt migration, and transmetalation between the resulting o-(2-exo-norbornyl)arylcobalt species and the arylzinc reagent
An expedient access to the first optically pure ruthenium complexes containing C1-symmetric cyclic (alkyl)(amino)carbene ligands is reported. They demonstrate excellent catalytic performances in asymmetric olefinmetathesis with high enantioselectivities (up to 92% ee). Preliminary mechanistic insights provided by density functional theory models highlight the origin of the enantioselectivity.
[EN] HIGHLY Z-SELECTIVE AND ENANTIOSELECTIVE RING OPENING/CROSS METATHESIS<br/>[FR] MÉTATHÈSE PAR OUVERTURE DE CYCLE/MÉTATHÈSE CROISÉE HAUTEMENT SÉLECTIVE ET ÉNANTIOSÉLECTIVE POUR Z
申请人:CALIFORNIA INST OF TECHN
公开号:WO2014186631A1
公开(公告)日:2014-11-20
This invention relates generally to enantiomerically enriched C-H activated ruthenium olefin metathesis catalyst compounds which are stereogenic at ruthenium, to the preparation of such compounds, and the use of such catalysts in the metathesis of olefins and olefin compounds, more particularly, in the use of such catalysts in enantio- and Z-selective olefin metathesis reactions. The invention has utility in the fields of catalysis, organic synthesis, polymer chemistry, and industrial and fine chemicals chemistry.
Reactivity and Selectivity in Hydrovinylation of Strained Alkenes
作者:Wang Liu、T. V. RajanBabu
DOI:10.1021/jo1015135
日期:2010.11.19
alkenes such as heterobicyclic [2.2.1]heptanes and cylobutenes. Reactions involving the heterobicyclic compounds are rare examples for this class of compounds where the metal-catalyzed C−C bond-forming reactions proceed without a concomitant ring-opening process. While the enantioselectivity in these systems remains modest, hydrovinylation of endo-5,6--bis-benzyloxymethylbicyclo[2.2.1]hept-2-ene gives
Ruthenium-catalyzed 1,4-Addition of Organoboronic Acids to α,β-Unsaturated Ketones
作者:Ryo Shintani、Tamio Hayashi
DOI:10.1246/cl.2008.724
日期:2008.7.5
A ruthenium-catalyzed 1,4-addition of organoboronic acids to α,β-unsaturatedketones has been developed. The use of 2-(di-tert-butylphosphino)biphenyl as the ligand in combination with [RuCl2(p-cym...