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Upstream product

• 37555-23-0 2-trifluoromethylsulfonyloxy-1-hexene 
• 17689-03-1 1-hexynyllithium 
• 3839-31-4 dimethyl(phenyl)silyllithium 
• 693-02-7 hex-1-yne 
• 201230-82-2 carbon monoxide 
• 766-77-8 Dimethylphenylsilane 
• 768-33-2 phenyldimethylsilyl chloride 
• 185990-03-8 dimethylphenyl(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)silane 
• 148991-51-9 hex-1-yn-1-yldimethyl(phenyl)silane 

Relevant academic research and scientific papers

Iridium(i) complexes bearing hemilabile coumarin-functionalised N-heterocyclic carbene ligands with application as alkyne hydrosilylation catalysts

A set of iridium(i) complexes of formula IrCl(κC,η2-IRCouR′)(cod) or IrCl(κC, η2-BzIRCouR′)(cod) (cod = 1,5-cyclooctadiene; Cou = coumarin; I = imidazolin-2-carbene; BzI = benzimidazolin-2-carbene) have beeen prepared from the corresponding azolium salt and [Ir(μ-OMe)(cod)]2 in THF at room temperature. The crystalline structures of 4b and 5b show a distorted trigonal bipyramidal configuration in the solid state with a coordinated coumarin moiety. In contrast, an equilibrium between this pentacoordinated structure and the related square planar isomer is observed in solution as a consequence of the hemilability of the pyrone ring. Characterization of both species by NMR was achieved at the low and high temperature limits, respectively. In addition, the thermodynamic parameters of the equilibrium, ΔHR and ΔSR, were obtained by VT 1H NMR spectroscopy and fall in the range 22-33 kJ mol-1 and 72-113 J mol-1 K-1, respectively. Carbonylation of IrCl(κC,η2-BzITolCou7,8-Me2)(cod) resulted in the formation of a bis-CO derivative showing no hemilabile behaviour. The newly synthesised complexes efficiently catalyze the hydrosilylation of alkynes at room temperature with a preference for the β-(Z) vinylsilane isomer.

Rh(I)/(III)-N-Heterocyclic Carbene Complexes: Effect of Steric Confinement Upon Immobilization on Regio- and Stereoselectivity in the Hydrosilylation of Alkynes

Rh(I) NHC and Rh(III) Cp* NHC complexes (Cp=pentamethylcyclopentadienyl, NHC=N-heterocyclic carbene=pyrid-2-ylimidazol-2-ylidene (Py?Im), thiophen-2-ylimidazol-2-ylidene) are presented. Selected catalysts were selectively immobilized inside the mesopores

Ru-Catalyzed Migratory Geminal Semihydrogenation of Internal Alkynes to Terminal Olefins

Semihydrogenation of alkynes to alkenes represents a fundamentally useful transformation. In addition to the well-known cis- and trans-semihydrogenation, herein a geminal semihydrogenation of internal alkynes featuring 1,2-migration is described, which pr

Immobilization of Pyrene-Adorned N-Heterocyclic Carbene Complexes of Rhodium(I) on Reduced Graphene Oxide and Study of their Catalytic Activity

Two pyrene-tagged N-heterocyclic carbene (NHC) complexes of rhodium(I) were obtained and characterized. The two complexes were supported onto reduced graphene oxide (rGO), generating two new materials in which the molecular complexes are immobilized by π–

Phosphoramidite complexes of Pd(II), Pt(II) and Rh(I): An effective hydrosilylation catalyst of 1-hexyne and 1-octene

The hydrophosphorane HP(OC6H4NMe)2 was used to prepare the diastereotopic complexes [MCl2{P(OC6H4NMe)OC6H4NHMe}] (M?=?Pd, Pt) by reaction with [MCl2(PhCN)2], and [RhCl(PPh3){P(OC6H4NMe)OC6H4NHMe}] by reaction with [RhCl(PPh3)3]. To form these complexes, the phosphorane undergoes ring-opening, whereby it is coordinated as the tautomeric neutral phosphoramidite-amino chelating ligand. The crystal structure of [RhCl(PPh3){P(OC6H4NMe)OC6H4NHMe}] was determined and the geometry about the Rh(I) atom is square-planar with cis-disposed phosphorus-donor ligands. The Rh–P distance is shortened (2.1056(6) ?) due to Rh(d)?→?P π-backbonding. In addition, [RhCl(PPh3){P(OC6H4NMe)OC6H4NHMe}] was shown to be an effective regio- and stereoselective catalyst for the hydrosilylation of 1-octene and 1-hexyne.

N-heterocyclic carbene-amide rhodium(I) complexes: Structures, dynamics, and catalysis

The amide-functionalized imidazolium salts [BocNHCH2CH 2ImR]X (R = Me, X = I, 1a; R = benzyl, X = Br, 1b; R = trityl, X = Cl, 1c) bearing increasingly bulky N-alkyl substituents were prepared in high yields by direct alkylation of the (2-imidazol-1-yl-ethyl)carbamic acid tert-butyl ester; 1c is a crystalline solid also characterized by X-ray diffraction. These salts are precursors for the synthesis of rhodium(I) complexes [Rh(NBD)X(NHC)] (NHC = 1-(2-NHBoc-ethyl)-3-R-imidazolin-2-ylidene; X = Cl, R = Me (3a), R = benzyl (3b), R = trityl (3c); X = I, R = Me (4a)). All the complexes display restricted rotation about the metal-carbene bond; however, while the rotation barriers calculated for 3a,b and 4a matched the experimental values, unexpectedly this was not true in the case of 3c, where the experimental value was equal to that obtained for compound 3b (58.6 kJ mol-1) and much smaller with respect to the calculated one (100.0 kJ mol-1). The catalytic activity of the neutral rhodium(I) complexes 3a-c in the hydrosilylation of terminal alkynes with HSiMe2Ph has been investigated with PhC≡CH, TolC≡CH, nBuC≡CH, Et 3SiC≡CH, and (CPh2OH)C≡CH as substrates. The steric hindrance on the N-heterocyclic ligand and on the alkyne substrates affects conversion and selectivity: for the former the best results were achieved employing the less encumbered 3a catalyst with TolC≡CH, whereas by employing hindered alkynes such as Et3SiC≡CH or (CPh 2OH)C≡CH the hydrosilylation leads only to the formation of the β-(E)-vinylsilane and α-bis(silyl)alkene isomers. The complexes 3a,b have also been employed in the addition of arylaldehydes with phenylboronic acid, and like in the hydrosylylation case, the best results were obtained using 3a in the presence of aldehydes bearing electron-withdrawing groups, such as 4-cyanobenzaldehyde and 4-acetylbenzaldehyde as substrates.

A simple route to chelating, structurally different triazole-based bis(N-heterocyclic carbene) ligands and their coordination to PtII

Two new bis(triazolium) salts have been prepared and used as N-heterocyclic carbene (NHC) precursors. The structure of the salts is highly dependent on the synthetic route, which implies the sequential alkylation of two of the three N atoms at the triazol

Copper-catalyzed highly regioselective silylcupration of terminal alkynes to form α-vinylsilanes

A highly regioselective synthesis of branched vinylsilanes through silicon-copper additions to terminal alkynes catalyzed by copper(I) was developed using methanol as additive. The corresponding vinylsilanes were obtained with excellent branched to linear selectivity of up to 99/1 in good yields.

Silylzincation of carbon-carbon multiple bonds revisited

The first investigation of the copper-catalyzed silylzincation of alkynes as well as a diene and styrene using bis(triorganosilyl) zinc reagents led to the development of an efficient procedure and the disclosure of an unexpected bissilylation and unfores

Hydrosilylation of 1-hexyne promoted by acetone solvated gold atoms derived catalysts

Supported gold nanoparticles, prepared by deposition of acetone solvated Au atoms on supports as carbon and γ-Al2O3, behave as valuable catalysts for the regioselective hydrosilylation of 1-hexyne with different silanes. The catalytic behaviour of gold-based systems is compared with the activity of supported platinum catalysts and a different affinity between the metals and the silanes is observed.