Borate hydrotris -, copper

Casarin M, Pandolfo L, Vittadini A. Carbonyl copper(I) complexes with hydrotris(l,2,4-triazolyl)borate, hydrotris(pyrazolyl)borate, and tris(pyrazolyl)methane Hgands. A DFT smdy. Phys Chem Chem Phys. 2009 11 94-96. 

For instance, the reaction of hydrotris(pyrazol-yl)borate-copper complex 15 (Scheme 5) with alkenes and ethyl diazoacetate results in the formation of cyclopropanes in yields in the range 63-78 % [19]. 

Figure 16 Structural diagram and 647.1-mn excitation RR spectrum of the blue copper site analog complex, LCu(ll)-SR (L = hydrotris(3,5-diisopropyl-l-pyrazolyl)borate). A single Cu-S stretching mode is seen in the RR spectrum, as expected from excitation into RS —Cu CT transition of a chromophore containing only one terminal Cu-S bond...

The reaction is carried out in a Schlenk tube, Fig. 1. Acetone (10 mL) is cooled in an ice bath and saturated with carbon monoxide by passing in a brisk stream of the gas for 10 minutes. Potassium hydrotris(pyrazolato)borate (252 mg, 1.0 mmole) and copper(I) chloride (99 mg, 1 mmole) are added to the acetone, and the mixture is stirred for 30 minutes while continuing to pass a slow stream of carbon monoxide. At the end of this period, the white suspension is filtered, using the Schlenk-type apparatus illustrated, Fig. 2, keeping the whole under an atmosphere of CO. The clear colorless filtrate is evaporated to dryness, and the cream-colored residue is extracted with 10 mL light petroleum (boiling range 40-60°, saturated with CO) and filtered. Evaporation of the solvent from the filtrate affords a white powder of Cu(CO)[(pz)3BH] (156 mg, 51%). 

BCuN6OCioH10, Copper , car-bonyl[hydrotris(pyrazolato)borato]-, 21 108 BCuN6OCi6H22, Copper , carbonyl[tris(3,5-dimethylpyrazolato)hydroborato]-, 21 109 BCuNsOCisHn, Copper , car-bonyl[tetrakis(pyrazolato)borato]-, 21 110 BNNaC2H3, Borate 1 -), cyanotri[(2//)hydro)-, sodium, 21 167... 

BN RhC44HM, Rhodium , tetrakis(l-isocy-anobutane)-, tetraphenylborate(l -), 21 50 BN C Hio, Borate(l -), hydrotris(pyrazolato)-, copper complex, 21 108 BN6Ci5H22, Borate(l -), tris(3,5-dimethylpyr-azolato)hydro-, copper complex, 21 109 BN8Ci2Hi2, Borate(l-), tetrakis(pyrazolato)-, copper complex, 21 110 BjFeN CjoH,, Iron(II), [tris[p.-[(l,2-cy-clohexanedione dioximato)-0 0 ]diphenyl-diborato(2 — )]-NJI JI" X " JI"",... 

Fig. 16. Resonance Raman spectra (647.1 nm excitation) of the blue copper site analog complex, LCuCIIlSCHfCHslC Hs [L is hydrotris(3,5-diisopropyl-l-pyrazolyl) borate], with natural abundance iec-butyl thiolate (top) and the C -deuterated isotopomer (bottom). ...

This was the first simple synthesis of crystalline poly(l,4-phenylene oxide) (PPO) having a melting point by the catalytic oxidative polymerization method, although other time-consuming synthesis procedures have been reported (94-96). As the tyrosinase model, (hydrotris(3,5-diphenyl-l-pyrazolyl)borate) copper [Cu(Tpzb)] complex (5) and (l,4,7-R3-l,4,7-triazacyclononane) copper [Cu(L ) R = isopropyl (iPr), cyclohexyl (cHex), and w-butyl (nBu)] complexes (6) were employed. 

It is noteworthy that the same reaction with a copper(I) complex with HB(3,5-iPr2Pz)3 causes an instantaneous formation of a dimeric J,-Ti Ti2-peroxo complex [118-120]. Thus, the more steric bulk of HB(3-tBu-5-iPrpz)3) inhibits the secondary reaction between the putative superoxo complex and a copper(I) counterpart generating a p.- n iti -peroxo dimer. While the employment of a N3 tripodal hydrotris(pyrazolyl)borate substantiates a side-on superoxo structure, the other complex prepared with a N4 ligand adopts a terminal coordination of the superoxide as indicated in Fig. 9. 

Studies on the hindered hydrotris(pyrazolyl)borate complexes of the Cu(CO) unit show a good correlation between vCO and the 5( Cu) NMR chemical shift. " CO adsorbed on CuCl film microcrystals shows vCO at 2134 cm -evidence for very weak Ti-interactions between CO and CuCl. " Several groups have reported studies on CO adsorption on copper centres supported in zeolites.147-150 values were used to probe structural changes in the CO-adduct of Cub in cytochrome bo, from E. coli ... 

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