Half-Lantern Pt(II) and Pt(III) Complexes. New Cyclometalated Platinum Derivatives

Inorganics

Violeta Sicilia¹  Pilar Borja² 

[1] Departamento de Química Inorgánica, Escuela de Ingeniería y Arquitectura de Zaragoza, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC—Universidad de Zaragoza, Edificio Torres Quevedo, Campus Río Ebro, Zaragoza 50018, Spain;Departamento de Química Inorgánica, Facultad de Ciencias, Instituto de Síntesis Química y Catálisis Homogénea (ISQCH), CSIC—Universidad de Zaragoza, Pedro Cerbuna 12, Zaragoza 50009, Spain; E-Mails:

关键词: half-lantern compounds;    cyclometalated;    platinum (II);    platinum (III);   

DOI  :  10.3390/inorganics2030508

来源: mdpi

【 摘 要 】

The divalent complex [{Pt(bzq)(μ-L)}₂] (1) [Hbzq = benzo[h]quinolone, HL = CF₃C₄H₂N₂SH: 4-(trifluoromethyl)pyrimidine-2-thiol] was obtained from equimolar amounts of [Pt(bzq)(NCMe)₂]ClO₄ and 4-(trifluoromethyl)pyrimidine-2-thiol with an excess of NEt₃. The presence of a low intensity absorption band at 486 nm (CH₂Cl₂), 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: Cl₂, Br₂ or I₂) to give the corresponding dihalodiplatinum (III) complexes [{Pt(bzq)(μ-L)X}₂] (L = CF₃C₄H₂N₂S-κN,S; X: Cl 2, Br 3, I 4). Complexes 2–4 were also obtained by reaction of 1 with HX (molar ratio 1:2, 10% excess of HX) in THF with yields of about 80% and compound 2 was also obtained by reaction of [{Pt(bzq)(μ-Cl)}₂] with HL (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 Pt₂(III,III)X₂ half-lantern complexes.

【 授权许可】

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