CO Extrusion in Homogeneous Gold Catalysis: Reactivity of Gold Acyl Species Generated through Water Addition to Gold Vinylidenes
作者:Janina Bucher、Tim Stößer、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1002/anie.201409859
日期:2015.1.26
describe a new gold‐catalyzed decarbonylative indene synthesis. Synergistic σ,π‐activation of diyne substrates leads to gold vinylidene intermediates, which upon addition of water are transformed into gold acyl species, a type of organogold compound hitherto only scarcely reported. The latter are shown to undergo extrusion of CO, an elementary step completely unknown for homogeneousgoldcatalysis. By tuning
Gold for the Generation and Control of Fluxional Barbaralyl Cations
作者:Paul R. McGonigal、Claudia de León、Yahui Wang、Anna Homs、César R. Solorio-Alvarado、Antonio M. Echavarren
DOI:10.1002/anie.201207682
日期:2012.12.21
comparison with the shape‐shifting barbaralylcation, which exists as a mixture of 181 400 degenerate forms. Gold‐catalyzed cycloisomerizations of 7‐alkynyl cyclohepta‐1,3,5‐trienes were found to proceed via fluxionalbarbaralyl intermediates (see scheme). The evolution of the intermediates into 1‐ or 2‐substituted indenes could be controlled by the choice of gold complex.
Low-valent Niobium-mediated Synthesis of Indenes: Intramolecular Coupling Reaction of CF<sub>3</sub>Group with Alkene C–H Bond
作者:Kohei Fuchibe、Ken Mitomi、Takahiko Akiyama
DOI:10.1246/cl.2007.24
日期:2007.1
CF3 group of o-alkenyl-α,α,α-trifluorotoluenes underwent intramolecular coupling reaction with the alkene C–H bond under NbCl5/LiAlH4 system. Substituted indenes were obtained in good yields.
Reactor blend polypropylene, process for the preparation thereof and
申请人:Montell Technology Company BV
公开号:US05747621A1
公开(公告)日:1998-05-05
Fractionable, reactor blend polypropylenes, directly obtainable from the polymerization reaction of propylene, having: (a) content of isotactic pentads (mmmm) comprised between 25 and 85%; (b) ratio M.sub.w,/M.sub.n <5; containing from 10 to 70% by weight of a fraction soluble in boiling diethyl ether, said fraction having a content of isotactic pentads (mmmm) comprised between 5 and 25%, and from 30 to 90% by weight of a boiling n-heptane-insoluble fraction, soluble in xylene at 135.degree. C., said fraction having a content of isotactic pentads (mmmm) comprised between 50 and 99%, are disclosed. These polymers are suitable as thermoplastic-elastomeric materials. A process for the preparation of these polymers and a process for the preparation of 2-aryl-substituted indenyl metallocene ligands is also disclosed.
Addition of Arylboronic Acids to Arylpropargyl Alcohols en Route to Indenes and Quinolines
作者:Jane Panteleev、Richard Y. Huang、Erica K. J. Lui、Mark Lautens
DOI:10.1021/ol202176g
日期:2011.10.7
A regio- and stereoselective rhodium-catalyzed synthesis of trisubstituted allylic alcohols is described. The utility of these synthons is demonstrated in a convenient synthesis of indenes and quinolines.