7650-81-9Relevant articles and documents
Versatile Visible-Light-Driven Synthesis of Asymmetrical Phosphines and Phosphonium Salts
Arockiam, Percia Beatrice,Lennert, Ulrich,Graf, Christina,Rothfelder, Robin,Scott, Daniel J.,Fischer, Tillmann G.,Zeitler, Kirsten,Wolf, Robert
supporting information, p. 16374 - 16382 (2020/11/03)
Asymmetrically substituted tertiary phosphines and quaternary phosphonium salts are used extensively in applications throughout industry and academia. Despite their significance, classical methods to synthesize such compounds often demand either harsh reaction conditions, prefunctionalization of starting materials, highly sensitive organometallic reagents, or expensive transition-metal catalysts. Mild, practical methods thus remain elusive, despite being of great current interest. Herein, we describe a visible-light-driven method to form these products from secondary and primary phosphines. Using an inexpensive organic photocatalyst and blue-light irradiation, arylphosphines can be both alkylated and arylated using commercially available organohalides. In addition, the same organocatalyst can be used to transform white phosphorus (P4) directly into symmetrical aryl phosphines and phosphonium salts in a single reaction step, which has previously only been possible using precious metal catalysis.
Efficient catalytic hydrogenation of levulinic acid: A key step in biomass conversion
Tukacs, Jozsef M.,Kiraly, David,Stradi, Andrea,Novodarszki, Gyula,Eke, Zsuzsanna,Dibo, Gabor,Kegl, Tamas,Mika, Laszlo T.
supporting information; experimental part, p. 2057 - 2065 (2012/08/14)
γ-Valerolactone (GVL) has been proposed as a sustainable liquid, and could be used for the production of hydrocarbons by using both homogeneous and heterogeneous catalytic systems. The selective reduction of levulinic acid (LA) to GVL is a key transformation for biorefinery concepts based on platform molecules. We report a detailed investigation of the conversion of LA to GVL using molecular hydrogen in the presence of a catalyst in situ generated from Ru(acac)3, and electronically and sterically characterized alkyl-bis(m-sulfonated-phenyl)- and dialkyl-(m-sulfonated-phenyl)phosphine (RnP(C6H4-m-SO3Na)3-n (n = 1 or 2; R = Me, Pr, iPr, Bu, Cp) ligands. The hydrogenation experiments were performed in the range of 5-100 bar H2 at 140 °C using 0.016 mol% catalyst and 5-20 eqv. of ligand. The effects of hydrogen pressure and Ru/ligand ratio on the LA conversion were determined. The nBuP(C 6H4-m-SO3Na)2 (χ = 12.5, Tol = 153°) showed the highest activity achieving turnover numbers up to 6200 with a yield and selectivity higher than 99% in a solvent, chlorine and promoter free reaction mixture. The catalyst was successfully recycled for six consecutive runs without loss of activity. The characterization of sulfonated and non-sulfonated phosphines indicated that the sulfonation had no significant effect on the steric and electronic properties of the ligands. The Royal Society of Chemistry 2012.
REACTIONS OF CYCLOALKYL CHLORIDES AND BROMIDES WITH DIPHENYLPHOSPHIDE IONS IN LIQUID AMMONIA
Nazareno, Monica A.,Palacios, Sara M.,Rossi, Roberto A.
, p. 421 - 426 (2007/10/02)
The reactions of cycloalkyl (butyl, pentyl, hexyl and heptyl) chlorides and bromides with diphenylphosphide ions were studied in liquid ammonia.Cyclobutyl chloride was unreactive, whereas the bromide reacted giving the substitution product cyclobutyldiphenylphosphine (isolated as the oxide) in good yields; this reaction was catalysed by light and partially inhibited by p-dinitrobenzene (p-DNB).Cyclopentyl, cyclohexyl and cycloheptyl chlorides did not react in the dark, but the substitution products were formed under irradiation, and these reactions were partially by p-DNB.The bromides reacted in the dark or under irradiation, and these reactions were inhibited by p-DNB.It can be then concluded that the reactivity of cycloalkyl halides depends on the ring size and the nucleofugal group.In addition, as the overall reactivity decreases, there is an increase in electron transfer reactions.
