The Isolation, Characterization, and Isomerization of cis- and trans-Bis(benzonitrile)dichloroplatinum(II)
The Isolation, Characterization, and Isomerization of cis- and trans-Bis(benzonitrile)dichloroplatinum(II)
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顺式和反式双(苯甲腈)二氯铂(II)的分离、表征和异构化
DOI：
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发表时间：
1981
期刊：
影响因子：
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通讯作者：
S. Kawaguchi
中科院分区：
文献类型：
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作者：
T. Uchiyama;Y. Toshiyasu;Yukio Nakamura;T. Miwa;S. Kawaguchi
氯化铂（II）与纯苄腈反应得到双（苄腈）二氯铂（II），其为根据温度以可变比例的顺式和反式异构体的混合物。色谱分离的异构体的几何形状确定的基础上的偶极距和IR数据。在CDCl 3中的13 C NMR光谱也使我们能够区分异构体之间的化学位移和耦合到氰化物碳的195 Pt，其共振峰被用来遵循异构化。在25 °C下，在CDCl 3中顺式到反式异构化的速率常数kc为（3.8±0.3）×10−6 s−1，比逆反应的速率常数kt=（2.9±0.2）×10−7 s−1大10倍。顺式和反式之间的平衡在25 °C下在CDCl 3中强烈倾向于反式，而在苯甲腈中，顺式形式在室温下是主要物种，而反式形式在较高温度下占主导地位。
The reaction of platinum(II) chloride with neat benzonitrile gave bis(benzonitrile)dichloroplatinum(II) as a mixture of cis and trans isomers in variable proportions, depending on the temperature. The geometry of the chromatographically separated isomers was identified on the basis of the dipole-moment and IR data. The 13C NMR spectra in CDCl3 also enabled us to discriminate between isomers in both chemical shift and coupling to the 195Pt of the cyanide carbon, the resonance peak of which was utilized to follow the isomerization. The rate constant (kc) for the cis-to-trans isomerization was found to be (3.8±0.3)×10−6 s−1 in CDCl3 at 25 °C, ten times larger than that [kt=(2.9±0.2)×10−7 s−1] of the reverse reaction. The equilibrium between cis and trans strongly favored trans in CDCl3 at 25 °C, whereas in benzonitrile the cis form was the dominant species at room temperature, while the trans form was dominant at higher temperatures.