Carbon monoxide insertion reactions. VI. Mechanisms of the reactions of methylmanganese pentacarbonyl and acetylmanganese pentacarbonyl with triphenylphosphine
Carbon monoxide insertion reactions. VI. Mechanisms of the reactions of methylmanganese pentacarbonyl and acetylmanganese pentacarbonyl with triphenylphosphine
复制标题
一氧化碳插入反应。
DOI：
10.1021/ic50060a037
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发表时间：
1968
影响因子：
4.6
通讯作者：
F. Calderazzo
中科院分区：
文献类型：
--
作者：
K. Noack;M. Ruch;F. Calderazzo
（CeH6）3（I）.顺式和反式异构体在核磁共振谱中有两个明显的乙酰质子峰，用硅胶色谱法分离了它们，并测定了富集色谱组分的红外光谱。红外C-0伸缩振动的数目分别是顺式和反式异构体的局部Cs和Civ对称性的预期数目。顺式异构体是反应的初始产物。顺反异构化速率符合一级动力学方程，在30 ℃时，k1 = 2.5 × 10~（-4）秒~（-1）。提出了一种涉及{CH 3-COMnfCOh}的分子间解离机理。这通过发现CH 3COMn-（CO）4P（C6H6）3的异构体混合物将膦配体与P（C6D5）3交换来证实。CHWCOMn-（CO）_3与三苯基膦反应的红外光谱研究表明，最终产物为CH_（313）COMn（CO）_4P（C_6H_5）_3的异构体混合物，其乙酰基位置保留有~（13）C标记。提出了该反应的离解机理。
(CeH6) 3 (I). The cis and trans isomers, which givetwo distinct acetyl proton peaks in nmr spectra, have been separated by chromatography on silica and the infrared spectra of enriched chromatographic fractions were measured. The number of infrared C-0 stretching vibrations is that expected for local Cs and Civ symmetries for the cis and the trans isomers, respec-kl tively. The cis isomer is the initial product of the reaction. The rate of isomerization cis trans follows a first-order kinetic equation with k\= 2.5 X 10-4sec-1 at 30 in acetone. A dissociative intermolecular mechanism involving {CH3-COMnfCOh} is proposed for the isomerization. This is confirmed by the finding that an isomeric mixture of CH3COMn-(CO) 4P (C6H6) 3 exchanges the phosphine ligand with P (C6D5) 3. The infrared study of the reaction between CHWCOMn-(CO) s and triphenylphosphine has shown that the final product is the isomeric mixture of CH313COMn (CO) 4P (C6H5) 3 with retention of 13C labeling at the acetyl position. A dissociative mechanism is proposed for this reaction.