Tribenzylphosphine oxide

Structural and Physical Aspects. - The stability of the various conformers of the phosphines oxides (269)- 211) has received theoretical consideration. A new triclinic polymorph of triphenylphosphine sulfide has been structurally characterised, together with a related triclinic polymorph of triphenylphos-phine. Two reports of the solid state crystal structure of the phenolic phosphine oxide (272) have appeared. A crystallographic study has confirmed that the product of electrochemical oxidation of o-diphenylphosphinoben-zenethiol is the disulfide-bridged bis(phosphine oxide) (273). Solid-state structural studies of the dioxides (274), the (i )-(-I-)-isomer of (275), 1-hexynyl(diphenyl)phosphine oxide,tribenzylphosphine oxide, and tris(t-butyl)phosphine selenide," have also been reported. 

Tribenzylphosphine oxide 184 A mixture of diphosphorus tetraiodide (10 mmoles) and benzyl iodide (60 mmoles) is heated gradually in an oil-bath. At 110° (internal temperature) a violent exothermic reaction sets in, the temperature rising to 170°. When the temperature has fallen again to 120° the mixture is heated at that temperature for a further 20 min. The dark mass, which solidifies, is stirred, with gentle warming, with saturated sodium sulfite solution or 2N-sodium hydroxide solution. The tribenzylphosphine oxide separates it is washed liberally with water (yield 95 %, m.p. 206-208°), and after recrystallization from ethanol has m.p. 212-213°. 

Alkylation of phosphorus by alkyl halides has also been carried out in the presence of free iodine (19). Thus, red phosphorus reacted exothermically with three equivalents of benzyl iodide and two equivalents of iodide at 110° to give (after hydrolysis) tribenzylphosphine oxide and dibenzylphosphmic acid in 81% and 7% yields, respectively. Similar results were obtained from benzyl chloride under these conditions. 

Tribenzylphosphine oxide, (C6H5.CH2)3PO.—Benzal chloride at 130° C. is treated with phosphonmm iodide in small quantities, when a violent reaction ensues the whole operation is conducted m a carbon dioxide atmosphere. A resinous mass results and this is decomposed by heating with water or alcohol. The reaction is represented by the following equations —... 

Emission-titration experiments for the Eu-(1) diacetate chloride in methanol solution were carried out with the following compounds in neutral or anionic form 1,10-phenanthroline 2,2 -bipyridine tribenzylphosphine oxide benzoic, 2-pyridine-carboxylic, 3-pyridinecarboxylic, 2-furancarboxylic, 2-thiophenecarboxylic, and 2-pyr-rolecarboxylic acids various pyridinedicarboxylic adds (2,3- 2,4- 2,5- 2,6- and 3,5-). These experiments showed that neutral ligands of the phenanthroline and bipyridine type do not enhance the Eu emission even though they produce intensely luminescent complexes with the free Eu(III) ion. Aromatic monocarboxylato ligands without heteroatoms readily replace the acetate(s) in the original substrate, as shown by the... 

A short strong H bond is present in the enol adamantane complex (13.35c) and an exceptionally short H bond of 2.32 A is found in the tribenzylphosphine oxide complex [(Ph CH2)3P02H]+ CUCI4 (13.35a). This latter H bond is nearly as short as that in the bi-hydroxide anion (13.35b). In both compounds (13.35a,c) the H atoms lie on crystallographic symmetry centres and appear to be symmetrical [31]. 

CftiH2aCeFi2NO8S4, Isoquinolinium tetrakis(4,4,4-trifluoro-1-(2-thienyl)butane-1,3-dionato)cerate(111), 40B, 949 Cn2H2 MoOg, Tris(9,10-phenanthrenequinone)molybdenum, 41B, 1139 Ca 2Hft 2CI2C0O2P2, Dichloro-bis(tribenzylphosphine oxide)cobalt(11), 45B, 1226... 

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