The divalent complex [{Pt(bzq)(μ-
L)}
2] (
1) [Hbzq = benzo[h]quinolone, H
L = CF
3C
4H
2N
2SH: 4-(trifluoromethyl)pyrimidine-2-thiol] was obtained from equimolar amounts of [Pt(bzq)(NCMe)
2]ClO
4 and 4-(trifluoromethyl)pyrimidine-2-thiol with an excess of
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The divalent complex [{Pt(bzq)(μ-
L)}
2] (
1) [Hbzq = benzo[h]quinolone, H
L = CF
3C
4H
2N
2SH: 4-(trifluoromethyl)pyrimidine-2-thiol] was obtained from equimolar amounts of [Pt(bzq)(NCMe)
2]ClO
4 and 4-(trifluoromethyl)pyrimidine-2-thiol with an excess of NEt
3. The presence of a low intensity absorption band at 486 nm (CH
2Cl
2), assignable to a metal-metal-to-ligand charge transfer transition (
1MMLCT) [dσ*(Pt)
2→π*(bzq)], is indicative of the existence of two platinum centers located in close proximity because the rigidity of the half-lantern structure allows the preservation of these interactions in solution. Compound
1 undergoes two-electron oxidation upon treatment with halogens
X2 (
X2: Cl
2, Br
2 or I
2) to give the corresponding dihalodiplatinum (III) complexes [{Pt(bzq)(μ-
L)
X}
2] (
L = CF
3C
4H
2N
2S-κN,S;
X: Cl
2, Br
3, I
4). Complexes
2–
4 were also obtained by reaction of
1 with H
X (molar ratio 1:2, 10% excess of H
X) in THF with yields of about 80% and compound
2 was also obtained by reaction of [{Pt(bzq)(μ-Cl)}
2] with H
L (4-(trifluoromethyl)pyrimidine-2-thiol) in molar ratio 1:2 in THF, although in small yield. The X-ray structures of
2 and
3 confirmed the half-lantern structure and the
anti configuration of the molecules. Both of them show Pt–Pt distances (2.61188(15) Å
2, 2.61767(16) Å
3) in the low range of those observed in Pt
2(III,III)
X2 half-lantern complexes.
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