Ernest Bekker Otricanie Smerti Pdf
Ryan, Joseph Kobler, Janine Bekker Carrig, Matthew Gonzalez, Billy Ferree, Tom King, Tom Kelly, Axel Avera, Victor Theander, John Sanchez, Don Covello. LITURGICAL MUSIC CORNER by our Music Director, Rebecca Brown Jan. 27th Third Sunday in Ordinary Time “The Spirit of the Lord is upon me, because he has anointed me to bring glad tidings to the.
A series of new, dicationic platinum(II) CNC pincer complexes were prepared and characterized by NMR and X-ray diffraction analysis. Oxidative addition of methyl iodide and iodine yielded the mostly unstable platinum(IV) complexes, which readily underwent reductive elimination to yield the platinum(II) precursors. Nonetheless, a platinum(IV) iodide adduct was isolated and was characterized by X-ray diffraction analysis. Additionally, a platinum(II) ethylene complex was isolated and found to be a moderately active yet highly selective catalyst in the co-dimerization of 2-methyl-2-butene with ethylene. Prodam melkashku bez dokumentov na.
CF 3–Ph reductive elimination from [(Xantphos)Pd(Ph)(CF 3)] ( 1) and [( i-Pr-Xantphos)Pd(Ph)(CF 3)] ( 2) has been studied by experimental and computational methods. Complex 1 is cis in the solid state and predominantly cis in solution, undergoing degenerate cis–cis isomerization (Δ G ≠ exp = 13.4 kcal mol –1; Δ G ≠ calc = 12.8 kcal mol –1 in toluene) and slower cis–trans isomerization ( Δ G calc = +0.9 kcal mol –1; Δ G ≠ calc = 21.9 kcal mol –1). In contrast, 2 is only trans in both solution and the solid state with trans-2 computed to be 10.2 kcal mol –1 lower in energy than cis-2. Kinetic and computational studies of the previously communicated ( J.
2006, 128, 12644), remarkably facile CF 3–Ph reductive elimination from 1 suggest that the process does not require P–Pd bond dissociation but rather occurs directly from cis-1. The experimentally determined activation parameters (Δ H ≠ = 25.9 ± 2.6 kcal mol –1; Δ S ≠ = 6.4 ± 7.8 e.u.) are in excellent agreement with the computed data (Δ H ≠ calc = 24.8 kcal mol –1; Δ G ≠ calc = 25.0 kcal mol –1).
Δ G ≠ calc for CF 3–Ph reductive elimination from cis-2 is only 24.0 kcal mol –1; however, the overall barrier relative to trans-2 is much higher (Δ G ≠ calc = 34.2 kcal mol –1) due to the need to include the energetic cost of trans–cis isomerization. This is consistent with the higher thermal stability of 2 that decomposes to PhCF 3 only at 100 °C and even then only in a sluggish and less selective manner. The presence of excess Xantphos has a minor decelerating effect on the decomposition of 1.
A steady slight decrease in k obs in the presence of 1 and 2 equiv of Xantphos then plateaus at [Xantphos]: 1 = 5, 10, and 20. Specific molecular interactions between 1 and Xantphos are not involved in this kinetic effect (NMR, T 1 measurements). A deduced kinetic scheme accounting for the influence of extra Xantphos involves the formation of cis-[(η 1-Xantphos) 2Pd(Ph)(CF 3)] that, by computation, is predicted to access reductive elimination of CF 3–Ph with Δ G ≠ calc = 22.8 kcal mol –1.