Experimental and theoretical studies on the course of CO insertion into Pt-C and Pd-C bonds in neutral and cationic complexes, [MR(Cl){P(CH3)3}2] and [MR{P(CH3)3}2(s)]+BF 4 - (M=Pt, Pd, R=CH3, C6H5, s=coordinated solvent)

Yoshihito Kayaki*, Hirokazu Tsukamoto, Masaki Kaneko, Isao Shimizu, Akio Yamamoto, Masanori Tachikawa, Takahito Nakajima

*この研究の対応する著者

    研究成果: Article査読

    26 被引用数 (Scopus)

    抄録

    Behavior of neutral and cationic cis- and trans-monoorganoplatinum complexes has been examined and compared with that of the corresponding monoorganopalladium complexes. The cis- and trans-monoorganoplatinum complexes having two trimethylphosphine ligands, [PtR(acetone){P(CH3)3}2]+BF 4 - (R=CH3 and C6H5) (4 and 5), have been prepared by removal of the chloride ligand in neutral complexes, [PdR(Cl){P(CH3)3}2] (2 and 3) with one equivalent of AgBF4. The cationic platinum complexes retaining the cis configuration of the parent neutral complexes, when prepared at low temperature, were found to be isomerized into the trans complexes 5 above -10°C for the methyl complex 5a and above -30°C for the phenyl complex 5b. Treatment of the cationic complexes 4 and 5 with CO gave no CO insertion product but afforded only the CO-coordinated trans-monoorganoplatinum complexes. The reluctance of the organoplatinum complexes toward CO insertion stands in contrast with the ease for the CO insertion of the corresponding organopalladium complexes. For clarifying the reasons of the marked difference between the behavior of the two Group 10 metal complexes the ab initio molecular orbital calculations with the MP2 level have been performed. We have found the transition states for the cis to trans isomerization of the three-coordinated cationic monoalkylplatinum complexes and for the CO insertion into the Pt-CH3 bond. The calculated barriers for the isomerization and CO insertion in the cationic organoplatinum complex are higher than those for the corresponding organopalladium complex in agreement with the experimental results showing the poor reactivity of the solvent-coordinated cationic organoplatinum complexes toward CO insertion compared to the organopalladium complexes. The reason for the difference in the reactivity between the palladium and platinum complexes can be ascribed to the relativistic effect of the platinum complexes.

    本文言語English
    ページ(範囲)199-209
    ページ数11
    ジャーナルJournal of Organometallic Chemistry
    622
    1-2
    DOI
    出版ステータスPublished - 2001 3月 9

    ASJC Scopus subject areas

    • 生化学
    • 無機化学
    • 有機化学
    • 物理化学および理論化学
    • 材料化学

    フィンガープリント

    「Experimental and theoretical studies on the course of CO insertion into Pt-C and Pd-C bonds in neutral and cationic complexes, [MR(Cl){P(CH3)3}2] and [MR{P(CH3)3}2(s)]+BF 4 - (M=Pt, Pd, R=CH3, C6H5, s=coordinated solvent)」の研究トピックを掘り下げます。これらがまとまってユニークなフィンガープリントを構成します。

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