(Sp)-1-Diphenylphosphanyl-2-{(S)-[2-(diphenylphosphanyl)phenyl]hydroxymethyl}ferrocene

The absolute configuration of the title compound, [Fe(C5H5)(C36H29OP2)], is Sp at the ferrocene group and S at the asymmetric C atom. Both P atoms have a trigonal-pyramidal conformation. There is a short intramolecular C-H...P contact with an H...P distance of 2.56 Å. The hydroxy group is involved in an intramolecular O-H...[pi]phenyl interaction. The crystal packing shows five very weak intermolecular C-H...[pi] contacts, with H...Cg distances between 3.26 and 3.39 Å (Cg is the centroid of a phenyl or cyclopentadienyl ring). Key indicators: single-crystal X-ray study; T = 162 K; mean σ(C–C) = 0.004 Å; R factor = 0.038; wR factor = 0.083; data-to-parameter ratio = 22.3

Dichlorido(3-phenyl­indenyl­idene)bis­(triphenyl­phosphane)ruthenium(II) tetra­hydro­furan disolvate

The RuII atom in the title compound, [RuCl2(C15H10)(C18H15P)2]·2C4H8O, has a distorted square-pyramidal conformation. The P and Cl atoms are at the base of the pyramid and the Ru—Cindenyl­idene bond is in the axial position. The two Cl ligands and the two phosphane ligands are in trans positions. The Cl—Ru—Cl and P—Ru—P angles are 157.71 (2) and 166.83 (2)°, respectively. The two independent tetra­hydro­furan (THF) solvent mol­ecules are disordered. One THF mol­ecule was refined using a split-atom model. The second THF mol­ecule was accounted for by using program PLATON/SQUEEZE [Spek (2009 ▶). Acta Cryst. D65, 148–155]. The molecular conformation shows three intramolecular C—H⋯Cl contacts and two C—H⋯π interactions while the crystal packing features an intermolecular C—H⋯Cl contact and two very weak intermolecular C—H⋯π contacts

NPG–TRIS Thermal Storage System. Quantification of the Limiting Processes: Sublimation and Water’s Adsorption

The NPG–TRIS binary system (NPG = (CH3)2C(CH2OH)2 = 2,2-dimetyl-1,3-propanodiol; TRIS = NH2C(CH2OH)3 = 2-Amino-2-(hydroxymethyl)-1,3-propanediol) was intensively investigated as a thermal energy storage system, due to the reversibility of its phase transitions and their associated energy. An adapted methodology was applied to precisely quantify its sublimation tendency. Relevant thermochemical data were revisited and evaluated using some specific experimental procedures. We also determined that the widely accepted requirement of working in an inert atmosphere to avoid deviations due to hygroscopicity is not necessary. Nevertheless, to take advantage of the energetic properties of the NPG–TRIS system, closed containers will be required to avoid NPG losses, due to its quantitatively determined high sublimation tendency.This study was financially supported by the Basque Government (IT1301-19, IT1364-19) and through the Elkartek18 R&D program, by the University of the Basque Country UPV/EHU (GIU19/019), and by the Ministry of Science and Innovation of Spain (PID2019-106644GB-I00

(R p)-1-{(R)-(Dimethyl­amino)[2-(diphenyl­phosphan­yl)phen­yl]methyl}-2-(diphenyl­phosphan­yl)ferrocene chloro­form solvate

The absolute configuration of the title mol­ecule, [Fe(C5H5)(C38H34NP2)]·CHCl3, is R,R p. The mol­ecular structure is similar to the structure of the solvent-free compound [Fukuzawa, Yamamoto & Kikuchi (2007 ▶). J. Org. Chem. 72, 1514–1517], but some torsion angles about the P—Cphen­yl bonds differ by up to 25°. The P atoms and the N atom have a distorted trigonal-pyramidal geometry. The chloro­form solvate group donates a C—H⋯π bond to the central benzene ring and is also involved in six inter­molecular C—H⋯Cl contacts with H⋯Cl distances between 2.96 and 3.13 Å

A Comparative Study of Dibenzylideneacetone Palladium Complexes in Catalysis

Commercial Pdx(dba)y from various suppliers was found to vary considerably in appearance, homogeneity, purity, and catalytic activity. The Buchwald–Hartwig amination of 4-bromoanisole (5) with aniline (6) was established as a sensitive test reaction to probe the efficiency of Pdx(dba)y batches in catalytic transformations. The yields obtained with 17 different Pdx(dba)y batches ranged from 10% to nearly quantitative and could not be predicted reliably on the basis of any physical or spectroscopic descriptor alone. The best results in the catalytic test reaction were consistently achieved with a self-made slowly crystallized Pd2(dba)3·toluene adduct. A protocol is disclosed that allows batches of Pdx(dba)y with unsatisfactory or inconsistent performance to be converted into this reliable precatalyst

Combustion synthesis of mechanically activated powders in the Ta-Si system

The effect of mechanical activation of reactants on the self-propagating high-temperature synthesis of TaSi2 and Ta5Si3 was investigated. SHS experiments were performed on mixtures of compositions Ta:Si = 1:2 and Ta:Si = 5:3 which had been milled for various times. For both compositions, mechanical activation had a large influence on the characteristics of the combustion process, particularly on the combustion peak temperature and wave velocity. The product composition depended on the initial stoichiometry and milling time. For the 5:3 stoichiometry, the product was single phase Ta 5Si3 (in its hexagonal and tetragonal forms) only when the powders were milled for sufficiently long milling times (>120 min). The 1:2 stoichiometry produced TaSi2 in a pure form, regardless of milling conditions. A mechanism for the combustion process is proposed on the basis of the microstructural evolution in quenched reactions

Simple synthetic routes to ruthenium-indenylidene olefin metathesis catalysts

An efficient synthetic protocol involving reactions between the free carbene and [RuCl(2)(PPh(3))(2)(Ind)] followed by addition of pyridine leads to the isolation of olefin metathesis active [RuCl(2)(L)(Py)(Ind)] (L = SIMes and SIPr) complexes. This novel approach circumvents the use of costly tricyclohexylphosphine