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• 2622-14-2 tricyclohexylphosphine 

Relevant academic research and scientific papers

Reaction of tertiary phosphine selenides, R3PSe (R = Me2N, Et2N or C6H11), with dibromine. The first reported examples of 1:1 addition

The R3PSeBr2 compounds (R = Me2N, Et2N or C6H11) have been prepared and characterised by 31P-{H} and infrared spectroscopy. The compounds R3PSeBr2 (R = Mes

Catalytic Metal-free Allylic C?H Amination of Terpenoids

The selective replacement of C?H bonds in complex molecules, especially natural products like terpenoids, is a highly efficient way to introduce new functionality and/or couple fragments. Here, we report the development of a new metal-free allylic amination of alkenes that allows the introduction of a wide range of nitrogen functionality at the allylic position of alkenes with unique regioselectivity and no allylic transposition. This reaction employs catalytic amounts of selenium in the form of phosphine selenides or selenoureas. Simple sulfonamides and sulfamates can be used directly in the reaction without the need to prepare isolated nitrenoid precursors. We demonstrate the utility of this transformation by aminating a large set of terpenoids in high yield and regioselectivity.

Phosphorus-Chalcogen Ring Expansion and Metal Coordination

The reactivity of 4-membered (RPCh)2 rings (Ch = S, Se) that contain phosphorus in the +3 oxidation state is reported. These compounds undergo ring expansion to (RPCh)3 with the addition of a Lewis base. The 6-membered rings were found to be more stable than the 4-membered precursors, and the mechanism of their formation was investigated experimentally and by density functional theory calculations. The computational work identified two plausible mechanisms involving a phosphinidene chalcogenide intermediate, either as a free species or stabilized by a suitable base. Both the 4- and 6-membered rings were found to react with coinage metals, giving the same products: (RPCh)3 rings bound to the metal center from the phosphorus atom in tripodal fashion.

Rapid phosphorus(III) ligand evaluation utilising potassium selenocyanate

Oxidative addition of SeCN- to tertiary phosphine ligands has been investigated in methanol at 298 K by use of UV-Vis stopped-flow and conventional spectrophotometry. In most cases kobsvs. [SeCN -] plots were linear with zero intercepts corresponding to a rate expression of kobs = k1[SeCN-]. Reactions rates are dependent on the electron density of the phosphorus centre with k 1 varying by five orders of magnitude from 1.34 ± 0.02 × 10-3 to 51 ± 3 mol-1 dm3 s-1 for P(2-OMe-C6H4)3 to PCy3 respectively. Activation parameters range from 27 ± 1 to 49.0 ± 1.3 kJ mol-1 for ΔH? and -112 ± 9 to -140 ± 3 J K-1 mol-1 for ΔS ? supporting a SN2 mechanism in which the initial nucleophilic attack of P on Se is rate determining. Reaction rates are promoted by more polar solvents supporting the mechanistic assignment. Reasonable linear correlations were observed between log k1vs. pKa, 1JP-Se and χd values of the phosphines. The reaction rates are remarkably sensitive to the steric bulk of the substituents, and substitution of phenyl rings in the 2 position resulted in a decrease in the reaction rate. The crystal structures of SePPh2Cy and SePPhCy2 have been determined displaying Se-P bond distances of 2.111(2) and 2.1260(8) respectively. The Royal Society of Chemistry 2008.

The Nature of the Bonding in Phosphane Tellurides. An Empirical NMR Study and the Crystal Structure of (iso-C3H7)3PTe

31P and 125Te NMR data of trialkylphosphane tellurides are compared.The deviation of the shifts for Me3PTe and t-But3PTe from those of other phosphane tellurides is interpreted in terms of high s-character of the P-Te bond originating from the phosphorus

A Single-Crystal ESR and Quantum Chemical Study of Electron-Capture Trialkylphosphine Sulfide and Selenide Radical Anions with a Three-Electron Bond

A low-temperature ESR study of electron-capture phosphoranyl radicals in X-irradiated single crystals of trialkylphosphine sulfides and selenides (R3PX: X=S, Se; R=CH3, C2H5, C6H11) is presented.The principal values and direction cosines of the g tensors