Reduction of phosphine oxides to the corresponding phosphine derivatives in Mg/Me3SiCl/DMI system

Mild Reduction of Phosphine Oxides with Phosphites To Access Phosphines

“…[5] Furthermore,i no rganometallic chemistry,t hey represent prime ligands to control most transition-metal-catalyzed reactions owings to their excellent metal ligation properties. [11] Such reaction conditions prevent scale-up and generate even more waste,m aking them not suitable for industrial use.In 2011, Laven and Kullberg patented an iodine-catalyzed reduction of aromatic phosphine oxides to phosphines at room temperature. [9] Ther eduction of phosphine oxides to phosphines is also important for the recycling of phosphorus resources.I np articular from an industrial standpoint, phosphine oxides are stoichiometric byproducts of the above-mentioned organic transformations, and are generally discarded as intractable waste in large quantities.T he reduction of phosphine oxides remains amethod of choice for the synthesis of P-chiral phosphines.…”

“…[9] Ther eduction of phosphine oxides to phosphines is also important for the recycling of phosphorus resources.I np articular from an industrial standpoint, phosphine oxides are stoichiometric byproducts of the above-mentioned organic transformations, and are generally discarded as intractable waste in large quantities.T he reduction of phosphine oxides remains amethod of choice for the synthesis of P-chiral phosphines. [11] Such reaction conditions prevent scale-up and generate even more waste,m aking them not suitable for industrial use. These procedures,h owever,r equire harsh reaction conditions and highly reactive and/or explosive reducing agents.C ÀPb ond cleavage also occurs as as ide reaction.…”

“…[10] Chemical reduction of phosphine oxides to phosphines has drawn alot of attention and has been performed with several reductants such as metal hydrides (e.g., hydrosilanes,LiAlH 4 , alane), low-valent metal reductants (e.g., SmI 2 /hexamethyl-phosphoramide,Cp 2 TiCl 2 /Mg,Sipowder), and organic reductants (e.g., hydrocarbon/activated carbon, hexaethylphosphorus triamide/POCl 3 ). [11] Such reaction conditions prevent scale-up and generate even more waste,m aking them not suitable for industrial use. [11] Such reaction conditions prevent scale-up and generate even more waste,m aking them not suitable for industrial use.…”

Green Synthesis and Theoretical Study of β‐Amino Esters via PPh3‐Catalyzed Mannich Reaction

“…Of note, the same catalysts, t‐BuOK or PPh 3 , under solvent‐free conditions afforded high yields of the target product (entries 9, 10, Table ). We preferred PPh 3 over tBuOK because it is a milder, weaker base with a pKa value 7.61 and therefore is easy to handle. In addition, it has already been used in asymmetrical synthesis…”

Mild Reduction of Phosphine Oxides with Phosphites To Access Phosphines

“…These procedures,h owever,r equire harsh reaction conditions and highly reactive and/or explosive reducing agents.C ÀPb ond cleavage also occurs as as ide reaction. [11] Such reaction conditions prevent scale-up and generate even more waste,m aking them not suitable for industrial use.In 2011, Laven and Kullberg patented an iodine-catalyzed reduction of aromatic phosphine oxides to phosphines at room temperature. [12] In essence,s acrificial electron-rich tributylphosphine is used for the capture of the oxygen atom from electron-deficient phosphine oxides.A side from the hazard, high cost, and instability of tributylphosphine, difficulties were encountered in separating it from some of the phosphine products.A ctually,t his very interesting reaction does not solve the industrial issue of waste treatment as anew phosphine oxide waste is created.Theu se of sacrificial triphenylphosphine to deoxygenate phosphine oxides has also been described, and triethylphosphite was found to be as competent an oxygen acceptor as triphenylphosphine.…”