Trioctylphosphine

Mixtures of trioctylamine and 2-ethylhexanol have been employed to extract 1—9% by volume acetic acid from its aqueous solutions. Reverse osmosis for acid separation has been patented and solvent membranes for concentrating acetic acid have been described (58,59). Decalin and trioctylphosphine were selected as solvents (60). Liquid—Uquid interfacial kinetics is an especially significant factor in such extractions (61). 

Other typical alkylphosphines that can be prepared through phosphine chemistry are monoisobutylphosphine [4023-52-3] trioctylphosphine [4731-53-7] monocyclohexylphosphiue [822-68-4] dicyclohexylphosphiue [829-84-5] and triethylphosphiue [554-70-1]. 

The O or S atoms in P=0 and P=S groups may act as electron donors although these groups form relatively weak complexes with electron acceptor compounds such as nonpolarizable, more electropositive (ie, hard) acids, including protons (14). Use is made of this property in the recovery of uranium from wet-process phosphoric acid by extractants such as trioctylphosphine oxide [78-50-2] and di(2-ethylhexyl) hydrogen phosphate [298-07-7]. 

Thorium, tetrakis(4,4,4-trifluoro-l-thienyl-l, 3-butanedione)(trioctylphosphine oxide)-structure, 1, 98 Thorium, triaquatetranitrato-structure, 1, 99... 

PBE dendrons coordinate to the surface of II-VI semiconductor nanocrystals (e.g., CdSe [33] and CdSe/ZnS core/shell structure [34, 35]) to modulate the photoluminescence of the nanocrystals [32]. Trioctylphosphine oxide (TOPO)-capped II-VI semiconductor nanocrystals of several-nanometers diameter have been synthesized by a pyrolysis reaction of organometallics in TOPO [33-35]. The capping ligand (TOPO) can be replaced by stronger ligands such as thiol compounds [36], suggesting that dendrons bearing sulfur atom(s) at the focal point replace TOPO as well. 

Talapin, D. V., Rogach, A. L, Kornowski, A., Haase, M. and Weller, H. (2001) Highly luminescent monodisperse CdSe and CdSe/ZnS nanocrystals synthesized in a hexadecylamine-trioctylphosphine oxide-trioctylphospine mixture. Nano Lett., 1, 207-211. 

Inoue, K. Nagamatsu, I. Baba, Y. Yoshizuka, K. Solvent extraction of platinum(TV) by trioctylphosphine oxide. Solvent Extr. Ion Exch. 1989, 7, 1111-1119. 

Hasegawa, Y. Kobayashi, I. Okuda, A. Solvent-extraction behavior of platinum(TV) and palladium(II) as chlorocomplex acids with trioctylphosphine oxide. Anal. Sci. 1991, 7, 377-381. 

Another study of the surface structure of CdSe NCs of 3.7 nm size used 31P MAS-NMR and 31P/77Se rotational-echo double-resonance (REDOR) to identify overlapping broad peaks from two surface species trioctylphosphine oxide (TOPO) at 29.3 ppm and trioctylphosphine selenide (TOPSe) at 22.2 ppm [343]. Both the isotropic chemical shift and CSA of the surface-bound TOPO were substantially different from those of the free ligand. Spin-echo experiments on 31P were stated to indicate an average P-P distance of 8-10 A at the surface, consistent with capping at alternate atomic sites (all Cd but not Se). 

Korkisch and Koch [106,107] determined low concentrations of uranium in seawater by extraction and ion exchange in a solvent system containing trioctyl phosphine oxide. Uranium is extracted from the sample solution (adjusted to be 1 M in hydrochloric acid and to contain 0.5% of ascorbic acid) with 0.1 M trioctylphos-phine oxide in ethyl ether. The extract is treated with sufficient 2-methoxyethanol and 12 M hydrochloric acid to make the solvent composition 2-methoxyethanol-0.1 M ethereal trioctylphosphine acid-12 M hydrochloric acid (9 10 1) this solution is applied to a column of Dowex 1-X8 resin (Cl" form). Excess of trioctylphosphine oxide is removed by washing the column with the same solvent mixture. Molybdenum is removed by elution with 2-methoxyethanol-30% aqueous hydrogen peroxide-12 M hydrochloric... 

The reactions used for synthesis of II-VI (CdSe, CdTe), III-V (InP, InAs), and IV-VI (PbS, PbSe, PbTe) semiconductor nanocrystals are outlined by Schemes 3-5.4,17,30-32 The syntheses are carried out at high temperatures, and in the presence of long-chain alkylphosphines (trioctylphosphine,TOP), alkyl-phosphine oxides (trioctylphosphine oxide, TOPO), alkylamines (hexadecyl-amine, HD A), and alkylphosphonic acids as the stabilizing agents. 

DEPA-TOPO [di (2-ethylhexyl) phosphoric acid and trioctylphosphine oxide] A process for recovering uranium from wet-process phosphoric acid, by solvent extraction with a mixture of the two named reagents. Developed at Oak Ridge National Laboratory and first commercialized in 1978 by Freeport Minerals Corporation and Wyoming Mineral Corporation. 

Mitsubishi have reported several processes based on Ru-catalyzed hydrogenation of anhydrides and acids. Succinic anhydride can be converted into mixtures of 1,4-butane-diol and y-butyrolactone using [Ru(acac)3]/trioctylphosphine and an activator (often a phosphonic acid) [97]. Relatively high temperatures are required ( 200°C) for this reaction. The lactone can be prepared selectively under the appropriate reaction conditions, and a process has been developed for isolating the products and recycling the ruthenium catalyst [98-100]. 

Tri-O-acylglycerols (TAGs), 70 281 Trioctylphosphine oxide (TOPO), 79 66 Triode gauge, 20 660-661 Triols, phosphine oxide, 77 501 Triorganohydridosilanes, in silicone chemistry, 22 555... 

A comparison of the basicities of Group VA element organic derivatives in nitro-methane solution showed that trioctylphosphine oxide (165 R = octyl) is a much weaker base than the corresponding amine oxide or hexamethylphosphoric triamide. 

Li+ Trioctylphosphine oxide + neutral carrier Lithium in blood serum and pharmaceuticals 136... 

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