Selective [1,4]-Hydrovinylation of 1,3-Dienes with Unactivated Olefins Enabled by Iron Diimine Catalysts.
Selective [1,4]-Hydrovinylation of 1,3-Dienes with Unactivated Olefins Enabled by Iron Diimine Catalysts.
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DOI：
10.1021/jacs.8b00245
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发表时间：
2018-03-07
影响因子：
15
通讯作者：
Chirik PJ
中科院分区：
文献类型：
--
作者：
Schmidt VA;Kennedy CR;Bezdek MJ;Chirik PJ
本文报道了α-二亚胺铁配合物催化共轭二烯与未活化α-烯烃的分子间[1，4]-加氢乙烯化反应。获得了具有排他性[1，4]-选择性的增值“跳过”二烯产物，并且观察到支链（Z）-烯烃产物的形成，而没有烯烃异构化的证据。用定义明确的单组分铁预催化剂（MesDI）Fe（COD）（MesDI =[2，4，6-Me 3-C6 H2-N=CMe]2）; COD = 1，5-环辛烷）进行的机理研究提供了对高选择性起源的见解。铁二烯络合物被鉴定为催化剂静止状态，并且分离和表征了一种这样的异戊二烯络合物（iPrDI）Fe（η4-C5 H8）。结合单晶X射线衍射、穆斯堡尔谱、磁性测量和密度泛函理论计算，确定该配合物最好描述为高自旋Fe（I）中心（SFe = 3/2）与α-二亚胺自由基阴离子（SDI = −1/2）进行反铁磁耦合，产生所观察到的S = 1基态。氘标记的实验和动力学分析的催化反应提供了支持的途径，涉及氧化环化的烯烃与二烯络合物，以产生铁金属乳酸盐。所观察到的选择性可以根据过渡态中用于氧化环化和随后的β-氢消除的竞争性空间相互作用来理解。
The selective, intermolecular [1,4]-hydrovinylation of conjugated dienes with unactivated α-olefins catalyzed by α-diimine iron complexes is described. Value-added “skipped” diene products were obtained with exclusive [1,4]-selectivity, and the formation of branched, (Z)-olefin products was observed with no evidence for alkene isomerization. Mechanistic studies conducted with the well-defined, single-component iron precatalyst (MesDI)Fe(COD) (MesDI =[2,4,6-Me3-C6H2-N=CMe]2); COD = 1,5-cyclooctadiene) provided insights into the origin of the high selectivity. An iron diene complex was identified as the catalyst resting state, and one such isoprene complex, (iPrDI)Fe(η4-C5H8), was isolated and characterized. A combination of single crystal X-ray diffraction, Mößbauer spectroscopy, magnetic measurements, and DFT calculations established that the complex is best described as a high-spin Fe(I) center (SFe = 3/2) engaged in antiferromagnetic coupling to an α-diimine radical anion (SDI = −1/2), giving rise to the observed S = 1 ground state. Deuterium-labeling experiments and kinetic analyses of the catalytic reaction provided support for a pathway involving oxidative cyclization of an alkene with the diene complex to generate an iron metallacycle. The observed selectivity can be understood in terms of competing steric interactions in the transition states for oxidative cyclization and subsequent β-hydrogen elimination.
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影响因子：
15
作者：
Biswas S;Page JP;Dewese KR;RajanBabu TV
通讯作者：
RajanBabu TV
影响因子：
15
作者：
Agapie, T;Schofer, SJ;Bercaw, JE
通讯作者：
Bercaw, JE
DOI：
10.1002/cber.19841170222
发表时间：
1984-01-01
期刊：
CHEMISCHE BERICHTE-RECUEIL
影响因子：
--
作者：
DIECK, HT;DIETRICH, J
通讯作者：
DIETRICH, J
用氧化还原活性双（Imino）吡啶铁配合物氧化添加碳碳键。
影响因子：
15
作者：
Darmon JM;Stieber SC;Sylvester KT;Fernández I;Lobkovsky E;Semproni SP;Bill E;Wieghardt K;DeBeer S;Chirik PJ
通讯作者：
Chirik PJ
影响因子：
4.6
作者：
Eisenberg, Richard;Gray, Harry B.
通讯作者：
Gray, Harry B.