Allylbenzene derivatives are ubiquitous frameworks in organic chemistry. Herein is described an efficient copper-catalyzed cross-coupling reaction using vinylsilanes and benzyl bromides, leading to the synthesis of allylbenzenes. This methodology allows the use of cis, trans and 1,1'-disubstituted vinylsilanes as well as a large number of sensitive moieties.
Copper-Catalyzed Cross-Coupling of Vinylsiloxanes with Bromoalkynes: Synthesis of Enynes
作者:Loïc Cornelissen、Maxime Lefrancq、Olivier Riant
DOI:10.1021/ol501140p
日期:2014.6.6
of various sensitive enynes. The use of cis, trans, and 1,1′-disubstituted vinylsiloxanes was allowed, and full retention of stereochemistry was observed. Sensitive groups such as halides, unsaturated ketones, and aldehydes were fully tolerated.
Synthetic and structural studies of NHC–Pt(dvtms) complexes and their application as alkene hydrosilylation catalysts (NHC=N-heterocyclic carbene, dvtms=divinyltetramethylsiloxane)
The synthesis and structuralcharacterization of a series of platinum complexes, bearing N-heterocyclic carbenes (NHC) and divinyltetramethylsiloxane (dvtms) as supporting ligands, are described. The reaction of commercially available Karstedt’s catalyst (Pt2(η2-ViSiMe2)2O}3) with in situ generated NHC leads to monomeric platinum(0) complexes in which one NHC is bound to the metal center, as indicated
A general protocol for the synthesis of Pt-NHC (NHC = N-heterocyclic carbene) hydrosilylation catalysts
作者:Benon P. Maliszewski、Nikolaos V. Tzouras、Sébastien G. Guillet、Marina Saab、Marek Beliš、Kristof Van Hecke、Fady Nahra、Steven P. Nolan
DOI:10.1039/d0dt03480k
日期:——
A general, user-friendly synthetic route to [Pt(NHC)(L)Cl2] and [Pt(NHC)(dvtms)] (L = DMS, Py; DMS = dimethyl sulfide, dvtms = divinyltetramethylsiloxane, Py = pyridine) complexes has been developed. The procedure is applicable to a wide range of ligands and enables facile synthetic access to key Pt(0)- and Pt(II)-NHC complexes used in hydrosilylation catalysis.
Expedient, Direct Synthesis of (L)Pt(0)(1,6-diene) Complexes from H<sub>2</sub>PtCl<sub>6</sub>
作者:Guillaume Berthon-Gelloz、Jean-Marc Schumers、Fabio Lucaccioni、Bernard Tinant、Johan Wouters、István E. Markó
DOI:10.1021/om7007088
日期:2007.11.1
The one-pot synthesis of useful [Pt-2(0)(eta(4) -1,6-diene)3] complexes, directly from H2PtCl6 center dot xH(2)O, has remained an unaddressed problem. We have found that the treatment of an i-PrOH solution of H2PtCl6 center dot xH(2)O by (Me3SiO)(2)MeSi(CH=CH2), in the presence of allyl ether (AE), followed by reaction of the in situ generated Pt(0) species with IPr carbene (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) enables the isolation of (IPr)Pt(AE) (1) in 50-70% yield. The scope of this method has been extended to other (L)Pi(1,6-diene) complexes (L = 1,3-dicyclohexylimidazol-2-ylidene, triphenylphoshine; 1,6-diene = diethyl 2,2-diallylmalonate (DAM)), and the molecular structure of the (IPr)Pt(DAM) (4) complex has been unequivocally determined by a single-crystal X-ray diffraction analysis. These results are significant for the formation of active L-Pt(0) fragments in catalysis.