Phosphorus-31 and carbon-13 solid-state NMR of tertiary phosphine-palladium complexes bound to silica

Single Site Supported Cationic Rhodium(I) Complexes for the Selective Redox Isomerization of Allylic Alcohols

“…It features as et of relativelym inor spinnings idebands, spaced by the magic-angle spinning (MAS)f requency.T he centerbandr evealed three components, markedb yt he dotted lines in the zoomed spectrumi nF igure 4b.T he two main peaks around2 8a nd 21 ppm stem from complex 3 and are tentatively assigned to each of the Pa toms showni nS cheme1.T he widths of the relatively broad 31 PNMR peaks are primarily dictated by structural disorder,a nd unresolved scalar couplings to 103 Rh. Besides am inor 31 PNMR peak at about 42 ppm, attributed to an oxidation product impurity (such NMR signals appear typically above 40 ppm [38,39] ), the absence of additional resonances reflects ap ure sample of complex 3.T he NMR spectrum reveals no traces of residual MeO-TPPMS (1b), which were observed to generate as harp 31 PNMR peak at À10 ppm (data not shown).…”

Heterogeneous Palladium Catalysts Applied to the Synthesis of 2- and 2,3-Functionalised Indoles

“…[53] The PdCl 2 {PPh 2 -(CH 2 ) 2 -SiCH 3 (OCH 2 CH 3 ) 2 } 2 was synthesized by reacting 2 equivalents of PPh 2 -(CH 2 ) 2 -SiCH 3 (OCH 2 CH 3 ) 2 with bis(benzonitrile)palladium dichloride at room temperature in dichloromethane by adapting a procedure reported elsewhere. [54] Preparation of [Pd(NH 3 ) 4 ] 2 þ /NaY [41] A 0. [42] Mesoporous SBA-15 type silica was used as support and was prepared by the acid-catalysed, non-ionic assembly pathway described by Margolese et al [55] The structure directing agent (Pluronic 123) was removed by calcination under air at 500 8C and the surfactant-free mesoporous silica was rigorously dried under a flow of nitrogen at 200 8C prior to the grafting reaction.…”

Application of Tripodal Linker Units to Immobilized Diphenylphosphine Palladium Complex Catalysts for Suzuki-Miyaura Coupling Reactions of Aryl Bromide: Effect of Immobilization Method of Phosphine Ligand on Catalytic Performance

“…Si, and 13 C CP/MAS NMR spectra of recovered 4(2)Pd after the catalysis as well as fresh 4(2)Pd. The peak corresponding to phosphine coordinated on palladium atom (P-Pd) was observed around 20 ppm 23) in the 31 P CP/MAS spectrum of 4(2) Pd before and after catalysis. No significant changes in the 31 P, 29 Si, and 13 C CP/MAS NMR peaks were observed before and after the catalysis, except for increased phosphine oxide.…”