Cobalt tetraphenylborate

C10fHg8BCO2P6S2 0.5 C3H7NO, Bis[(M"thio)(1,1,1 tris((diphenylphos-phino)methyl)ethane)cobalt] tetraphenylborate dimethylformamide solvate, 46B, 1241... 

CgeHe2BC0N2OP3, Nitrosyl(tris(2-diphenyIphosphinoethyl)amine)cobalt tetraphenylborate, 42B, 999... 

C-1 oBHeoBCOiiOi aPflSb CH2CI2, M Antimoniotetrakis[ tricarbonyl (tri-phenylphosphine)cobalt] tetraphenylborate dichloromethane solvate, 45B, 1389... 

CiaoHiiaAsaBaCOaPef M Cyclo-triarsenic bis[1,1,1-tris(diphenylphos-phinomethyl)ethane-cobalt] tetraphenylborate, 45B, 1390... 

The organic solvent should feature a low solubility in water and a high dielectric constant. Numerous studies have been reported for liquid-liquid junctions involving DCE [43,62,70,71,73], nitrobenzene [67,68,74,75], and nitrophenyloctylether (NPOE) [56]. Various hydrophobic electrolytes have been employed in these solvents. Tetraphenylarsonium (TPAs+) [[71,75,76], bis-triphenylphosphoranylidene (BTPPA+) [43,50], and hydrophobic tetra-arylammonium [77,78] are among the cations used in the organic phase. The choice for anions has been mostly restricted to borate derivatives, tetraphenylborate (TPB ) [70,79,80], tetrakis(4-chlorophenyl)borate (TPBCH) [43,81,82], and tetrakis(penta-fluoro)phenylborate (TPFB ) [49,83], as well as dicarbollyl-cobaltate [75]. 

Cesium is determined as the tetraphenylborate, total cobalt as the anthranilate, sulfate as barium sulfate, and cobalt(III) by addition of the alum to excess of potassium iodide solution followed by titration with thiosulfate- Anal. Calcd. -for CsCo(S04)2-12H20 Cs, 22.2 Co, 9.82 S04, 32.0. Found Cs, 22.2 Co, 9.83 S04, 32.3 Co(III), 9.80. 

The photochemistry of the water-insoluble [Co(sep)](B(C6H5)4)3 complex was studied in aprotic solvents (THF, AN, and DMF) [309]. When THF solution was irradiated with visible light, the cobalt(III) complex has been reduced by the tetraphenylborate anion to give a white [Co(sep)](B(C6H5)4)2 precipitate. From the residual solution biphenyl and phenol were isolated as the main products. This photoreaction proceeded much slower in DMF solution. 

Preconcentration of trace cobalt with the ion pair of 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol and tetraphenylborate onto microcrystalline naphthalene or column method and its determination by derivative spectrophotometry has been described [5]. The method was applied to the determination of trace Co in alloys and biological materials. 

Figure 5. Absorption spectrum of pentaammine (S)-2-chloropropionato cobalt-(III) tetraphenylborate in ("lower set) water (as ClOf salt), hexamethylphosphor-triamide (hmpa), dimethyl sulfoxide, N-metkylformamide (nmf), N,N-dimethyl-formamide (dmf) ("upper set) acetonitrile, methanol, ethanol, acetone, pyridine (py) and tetrahydrofuran (thf). The reference contained tetraphenylborate (as Na salt) at the same concentration as the solution of the complex.

Figure 6. CD spectrum of pentaammine (S)-2-chloropropionato -cobalt(III) tetraphenylborate in various solvents. Abbreviations are as for Figure 5. In water, the perchlorate salt was used.

The diiodo complex, /ra j-[Col2(TTP)], is prepared by air oxidation anhydrous cobalt(II) iodide is stirred with the ligand in nitromethane, Whereby a cobalt complex containing tetrahedral Coll" species is formed, which is then isolated by adding ether. The complex is redissolved in nitromethane and exposed to air for a few days. Successive additions of sodium tetraphenylborate and ether precipitates the desired compound. 

The instability of the quasi-organometallic donor anion tetraphenylborate (Ph4B ) has been exploited in a number of photochemical [216-218] and photolithographic [219] applications. The role of tetraphenylborate is exemplified in the photoreduction of the dimeric cobalt(fulvalene) complex, i.e. 

Cs ijHs BC0 2NaNa06, Bis- (N,N -ethylene-bis (salicylideneiminato)cobalt-(II))-bis-tetrahydrofuran-sodium(l) tetraphenylborate, 40B, 671 CesHy2Cl2MgN12O1af Magnesium hexa-antipyrine perchlorate, 32B, 324 CeeHesBrN1oNaO11, Sodium (phe(4)-val(6))antamanide bromide ethanol solvate, 40B, 671... 

C3 bHi, 2 620, (M Oxo)-bis(tris(M trimethylene)-ferrocene), 46B, 886 C3 9H3 sBFe203S, M"Ethylthio-M -carbonyl-bisCij-cyclopentadienyicarbon-yliron)(Fe-Fe) tetraphenylborate, 44B, 773 C39H37C0, (Tj -Cyclopentadienyl) (rj -1,3-dimesityl-2,4-diphenylcyclo-butadiene)cobalt, 45B, 988... 

CS5H67B2CU2N9O2 f (M Histamine)-bis[histamine(carbonyl)copper(I)] bis(tetraphenylborate), 46B, 1138 Cs6HssN6P2Pt, cis-Bis(1,3-diphenyltriazenido)bis(triphenylphos-phine)platinum(II) benzene solvate, 42B, 874, 998 CssHt2C1 NisNi204, M Chloro-bis(chlorotetra(benzimidazole)nickel-(II)) chloride-4-acetone, 33B, 435 C72H5sCl1sCoNioOi0 f trans-Tetrakis(miconazole)cobalt(II) nitrate, 44B, 958... 

CgeHe7BC0NO3P3S 0.5 CH2CI2, (Ethylsulfito)(tris(2-diphenylphos-phinoethyl)amine)cobalt(II) tetraphenylborate - 0.5 methylene chloride, 44B, 1049... 

Cl 32H1211B2CO2P6S2 2 C3H6O, Bis[(M methylthio)(l,l,l-tris((diphen-y Iphosphi no) me thy 1) ethane ).cobalt] bis (tetraphenylborate) acetone solvate, 46B, 1241... 

Cy 3HS0CI4P4RU2S, Thiocarbonylbis(triphenylphosphine)ruthenium-tri-/n-chloro-chlorobis(triphenylphosphine)ruthenium, 40B, 1068 Cy 3Hy0BC0INP3, Iodo(tris-(2-diphenylphosphinoethyl)amine)cobalt(II) tetraphenylborate toluene, 41B, 1214 Cy4H6oA92N2P4S2 r ThiocyanatobisUriphenylphosphine)siIver(I), 39B,... 

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