Hexafluoro-2,4-pentanedionato l- platinum II

The infrared and 1H nmr spectra of Pt(acac)2 are essentially the same as reported in the literature.6 The absorption spectrum in dichioromethane solution exhibits absorption maxima at 287 (e = 6840) and 346 nm (e = 3570). 

Both trans and cis-Pt(tfac)2 are air stable and sublime at 97-101° and 108-111°, respectively. They are soluble in most organic solvents, such as benzene, dichioromethane, diethyl ether, and acetone, solubilities of the cw-isomer being much larger than those of the rrans-isomer. 

The infrared spectra in Nujol in the 4000-700 cm-1 region are similar for the two isomers, although the y(C 0) and v(C C C) energies are a little lower for the trans-isomer [1580 (vs) broad and 1517 (vs) cm-1 ] than for the cis-isomer [1590 (vs) broad and 1530 (vs) cm-1 ]. In the lower frequency region the trans-isomer exhibits a single band at 458 cm 1, while the c/s-isomer has two bands at 461 and 446 cm-1, which may be related to the v(Pt—O) vibration. 

Both of the isomers show an absorption maximum in dichioromethane at 309 nm accompanied by shoulders at 330 and 390 nm, but the molar extinction coefficients are different, e(trans) being 5280 and e(c/s) 5570. Mass spectra of both isomers exhibit the parent peak at m/e = 501 in accordance with the calculated molecular weight of 501. 

The crystals of Pt(hfac)2 are air stable and sublime at around 65°, exhibiting the parent peak in the mass spectrum at m/e = 609 in accordance with the cal- 

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