31398-95-5Relevant academic research and scientific papers
Poly(p-phenylenediethynylene phosphane): A Phosphorus-Containing Macromolecule that Displays Blue Fluorescence Upon Oxidation
Rawe, Benjamin W.,Gates, Derek P.
, p. 11438 - 11442 (2015/10/13)
Despite the challenges associated with their synthesis, hybrid inorganic-organic polymers featuring heavier main-group elements spaced by π-conjugated organic functionalities have garnered considerable recent attention due to their chemical functionality and novel photophysical properties. We have succeeded in the preparation of an unprecedented organophosphorus polymer possessing functional phosphane-di-yne moieties in the main chain. Namely, poly(p-phenylenediethynylene phosphane) (PPYP) is prepared using a nickel(II)-catalyzed P-C bond-forming reaction. The hexyl-substituted PPYPs are solution processible and have been thoroughly characterized (molecular weight, Mw, ca. 104Da vs. polystyrene; degree of polymerization, DP, ca. 10). Remarkably, although PPYP shows very weak emission upon irradiation with UV light, its oxide shows blue "turn-on" fluorescence. The present discovery bridges the areas of main-group and polymer science and opens the door to a new class of σ-π-conjugated macromolecules with unique chemical functionality.
Direct conversion of phosphonates to phosphine oxides: An improved synthetic route to phosphines including the first synthesis of methyl JohnPhos
Kendall, Alexander J.,Salazar, Chase A.,Martino, Patrick F.,Tyler, David R.
supporting information, p. 6171 - 6178 (2015/02/19)
The synthesis of tertiary phosphine oxides from phosphonates was achieved reliably and in good to excellent yields using stoichiometric amounts of alkyl or aryl Grignard reagents and sodium trifluoromethanesulfonate (NaOTf). In the absence of the NaOTf additive, covalent coordination oligomers of magnesium and phosphorus species dominate the reaction, producing very low yields of phosphine oxide, but high conversions of the phosphonate starting material. Mechanistic studies revealed that a five-coordinate phosphorus species - not a phosphinate - is the reaction intermediate. A diverse array of phosphonates was converted to phosphine oxides using a variety of Grignard reagents for direct carbon-phosphorus functionalization. This new methodology especially simplifies the synthesis of dimethylphosphino (RPMe2)-type phosphines by using air-, water-, and silica-stable intermediates. To highlight this reaction, a new Buchwald-type ligand ([1,1′-biphenyl]-2-yldimethylphosphine, or methyl JohnPhos) and a classic bidentate phosphine, bis(diphenylphosphino)propane (dppp), were synthesized in excellent yields.
