Tri-n-octylphosphine oxide

Tri-n-octylphosphine oxide [78-50-2] M 386.7, m 59.5-60°, pK jt <0. Mason, McCarty and Peppard [J Inorg Nuclear Chem 24 967 7962] stirred an O.IM solution in benzene with an equal volume of 6M HCl at 40° in a sealed flask for 48h, then washed the benzene solution successively with water (twice), 5% aq Na2C03 (three times) and water (six times). The benzene and water were then evaporated under reduced pressure at room temperature. Zingaro and White [J Inorg Nucl Chem 12 315 7960] treated a pet ether solution with aqueous KMn04 (to oxidise any phosphinous acids to phosphinic acids), then with sodium oxalate, H2SO4 and HCl (to remove any manganese compounds). The pet ether solution was slurried with activated alumina (to remove phosphinic acids) and recrystd from pet ether or cyclohexane at -20°. It can also be crystd from EtOH. 

Bis(alkyldithio-/selenocarbamates) of Zn(ID and Cd(II) have previously been used in many applications including the rubber industry 1 and in analysis,382 as well as for single-molecular precursors in the growth of II VI thin films by CVD, as described earlier.181,383 They have also been shown to be good precursors for the preparation of II VI nanoparticles, in a process that involves their decomposition in a high-boiling donor solvent such as tri-n-octylphosphine oxide or 4-ethylpyridine (Figure 47). 

Kopping JT, Patten TE (2008) Identification of acidic phosphorus-containing ligands involved in the surface chemistry of CdSe nanoparticles prepared in tri-n-octylphosphine oxide solvents. J Am Chem Soc 130 5689-5698... 

The molecules producing coordinative saturation need not be chelating. As a by-product to the study of synergism in the extraction of alkali metal chelate salts, Healy (14) isolated crystalline complexes Li(PhCO-CHCOPhJSa where S = tri-n-octylphosphine oxide or N, N-dibutyl-acetamide. 

Compared with the variety of existing carbon or nitrogen nucleophiles that were subjected to nucleophilic addition to there are few examples for phosphorus nucleophiles. Neutral trialkylphosphines turn out to be to less reactive for an effective addihon to Cjq even at elevated temperatures [114], Trialkylphosphine oxides show an increased reactivity. They form stable fullerene-substituted phosphine oxides [115] it is not yet clear if the reaction proceeds via a nucleophilic mechanism or a cycloaddition mechanism. Phosphine oxide addition takes place in refluxing toluene [115], At room temperature the charge-transfer complexes of with phosphine oxides such as tri-n-octylphosphine oxide or tri-n-butylphosphine oxide are verifiable and stable in soluhon [116],... 

Highly monodisperse CdSe/CdS core/shell nanoparticles have been prepared by thermolysis in tri-n-octylphosphine oxide (TOPO) using [Cd(Se2CNMe( Hex))2] (250 °C for 30 min) and [Cd(S2CNMe( Hex))2] (250 °C for 30 min) as single-molecule precursors in a one-pot synthesis [118,119]. [Cd(Se2CNMe(Hex))2] (0.8 g) was dissolved in trioctylphos-... 

Tri-n-octylphosphine oxide (TOPO) has been the most popular phosphine oxide to be used as an extractant for the determination of iron, uranium, plutonium, molybdenum, titanium and thorium among other metals.43 44... 

For tri-n-octylphosphine oxide, for example, the shift in the P=0 stretching frequency from its value for the free extractant is greater for the hafnium complex (85 cm-1) than for the zirconium complex (70 cm-1).297... 

Petkovic, D.M. Kopecni, M.M. Mltrovic, A.A. Solvent extraction of nitric, hydrochloric and sulfuric acid and their uranyl salts with tri-n-octylphosphine oxide, Solvent Extr. Ion Exch. 10 (1992) 685-696. 

Shamsipur, M. Ghiasvand, A.R. Yamini, Y. Solid-phase extraction of ultratrace uranium(VI) in natural waters using octadecyl silica membrane disks modified by tri-N-octylphosphine oxide and its spectrophotometric determination with dibenzoylmethane, Anal. Chem. 65 (1999)4892 1895. 

Separation by solvent extraction Uranium can be extracted from aqueous solutions using extraction agents into the solvent phase, from which it can be stripped. The extraction agents used are phosphorus compounds such as di-(2-ethylhexyl)-phosphate, tri-n-butyl-phosphate and tri-n-octylphosphine oxide as well as primary, secondary and tertiary amines in salt form or as quaternary ammonium salts. The extraction agents are diluted with inert hydrocarbons, preferably kerosene, to concentrations of 4 to 10% by volume. The solubility of the amine salts, particularly the hydrogen sulfates, chlorides and nitrates is increased by adding long chain alcohols (e.g. isodecanol). 

The routine synthesis of well-defined semiconductor nanocrystallites was really opened up in a landmark paper by Murray, Norris and Bawendi [34]. They reacted solutions of dimethylcadmium (CH3)2Cd (in tri-n-occtylphosphine TOP) and tri-n-octylphosphine selenide (TOPSe) in hot tri-n-octylphosphine oxide (TOPO) in... 

TOP tri-n-octylphosphine TOPO tri-n-octylphosphine oxide HDA hexadecylamine ODE octadecene... 

We have used tri-n-octylphosphine oxide (TOPO) as a solvent extractant of uranium(VI) and thorium(IV) from nitric and hydrochloric acid solutions (1-3). In contrast, the extraction of uranium(VI) and thorium(IV) from nitric and hydrochloric acid solutions has been investigated by tri-n-butylphosphate (TBP) (4, 5). However, since TBP reveals a poor efficiency for the extraction of metals from sulphuric acid solutions, this paper extends the work to the extraction of uranium(VI) from sulphuric acid solutions by TOPO. 

---