Different bonding modes of sulfur bis-ylides in Pd complexes: Crystal structure of [Pd(μ-OAc){μ-[CH(SMe₂)]₂C(O)}(acac-O,O′)₂]ClO₄

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• 作者：E. Serrano ; T. Soler ; R. Navarro ; Esteban P. Urriolabeitia
• 关键词：Sulfur ylides ; Palladium ; CH-bond activation ; Crystal structure ; NMR
• 刊名：Journal of Molecular Structure
• 出版年：2008
• 出版时间：12 November 2008
• 年：2008
• 卷：890
• 期：1-3
• 页码：57-62
• 全文大小：273 K

文摘

The reaction of [Me₂SCH₂C(O)CH₂SMe₂]Br₂ (1) with Pd(OAc)₂ gives the mononuclear neutral complex cis-[PdBr₂{ηp>2p>-[CH(SMe₂)]₂C(O)}] (2) through double deprotonation of the bis-sulfonium salt. The sulfur bis-ylide coordinates in (2) as a C,C′-chelating ligand, and is obtained as a single diastereoisomer (meso form, RS/SR), in spite of the presence of two stereogenic ylidic centers. Reaction of (2) with AgClO₄ and Tlacac gives [Pd(acac-O,O′){ηp>2p>-[CH(SMe₂)]₂C(O)}]ClO₄ (3), which shows the same bonding mode for the bis-ylide ligand. However, (2) reacts with Pd(OAc)₂, AgClO₄ and Tlacac to give the dinuclear [Pd(μ-OAc){μ-[CH(SMe₂)]₂C(O)}(acac-O,O′)₂]ClO₄ (4) as two different isomers. In complex (4) the bis-ylide bridges two palladium atoms and the presence of two isomers arise from the relative arrangement of the bis-ylide with respect to the acetate ligand. The X-ray crystal structure of (4) has been determined.