Synthese von Alkin-, Alkinyl-und Vinyliden-Rhodium-Komplexen ausgehend von Alkinyltriphenylsilanen [1] / Synthesis of Alkyne, Alkynyl and Vinylidene Rhodium Complexes from Alkynyltriphenylsilanes [1]

Abstract

This paper treats the stability of two superposed gravitating streams rotating about the axis transverse to the horizontal magnetic field. The critical wave number for instability is found to be affected by rotation for propagation perpendicular to the axis about which the system rotates. The critical wave number for instability is not affected by rotation when waves propagate along the axis of rotation. The critical wave number is affected by both the magnetic field and the streaming velocity in both cases. Both the magnetic field and the rotation are stabilizing, while the streaming velocity is destabilizing.

Reactions of the Square-Planar Compounds Ir(C2Ph)L2(PCy3) (L2 = 2 CO, TFB) with HSiR3 (R = Et, Ph) and Hx+1SiPh3-x (x = 1, 2): Stoichiometric and Catalytic Formation of Si−C Bonds

“…In this context, it should be noted that Werner et al. have recently observed that not only 1-alkynes HC⋮CR but also the trialkylsilyl derivatives RC⋮CSiR‘ 3 can be transformed in the coordination sphere of rhodium into the isomeric disubstituted vinylidenes, :CC(SiR‘ 3 )R. The position of the triphenylsilyl group at the α-carbon atom of the alkenyl ligand of 11 rules out the possible participation of a vinylidene intermediate. In addition, it should be mentioned that 11 is the kinetically favored compound from the reaction of 6 with HSiPh 3 .…”

Silyl Migration of Me3SiCCPh Coordinated to [RuH(CO)(PtBu2Me)2]BAr‘4Can Be Reversed: Synthesis and Structure of [Ru(CHC(SiMe3)(Ph))(CO)(PtBu2Me)2]BAr‘4

“…There is a plethora of reports on isomerization of terminal alkynes on late transition metal centers to give metal vinylidene complexes, which have found some applications in organic synthesis . Less frequent is the isomerization of silyl alkynes on 14-electron fragments (i.e., RhClL 2 , IrClL 2 , and RuCl 2 L 2 ; L = phosphine) to corresponding vinylidenes (eq 1) . Computational studies suggested that a 1,2-H (or SiR 3 ) shift is energetically very costly, and it has been proposed that bimolecular H transfer is an alternative .…”

Alkynes and Diynes as Precursors for Organoiridium Complexes Containing Iridium−Carbon Single and Double Bonds,1

“…We have recently shown that not only terminal alkynes HC⋮CR but also trimethylsilyl-, triphenylsilyl-, and triphenylstannyl-substituted derivatives XC⋮CR (X = SiMe 3 , SiPh 3 , SnPh 3 4 ) can be converted in the coordination sphere of rhodium(I) to the corresponding vinylidenes . The metal-assisted isomerization proceeds either thermally or photochemically and occurs more rapidly for X = SnPh 3 than for X = SiMe 3 or SiPh 3 .…”