Neutral and cationic Fe(II) β-diketiminate complexes
摘要:
The three-coordinate, 12-valence electron complexes [((BDK)-B-Me)FeR] ((BDK)-B-Me = [HC(C(Me)NAr)(2)](-), Ar = 2,6-iPr(2)C(6)H(3), R = CH2Ph, CH2SiMe3) are reported as well as their reactivity towards Lewis bases. With perfluoroaryl borane and -borate type activators, the monoalkyls react to give alkyl-free paramagnetic cationic iron species counterbalanced by perfluorinated arylborate anions. The paramagnetic nature of the cations permits the observation of weak and dynamic interactions with these anions via F-19 NMR spectroscopy. (c) 2005 Elsevier B.V. All rights reserved.
Iron Catalyzed Double Bond Isomerization: Evidence for an Fe
<sup>I</sup>
/Fe
<sup>III</sup>
Catalytic Cycle
作者:Callum R. Woof、Derek J. Durand、Natalie Fey、Emma Richards、Ruth L. Webster
DOI:10.1002/chem.202004980
日期:2021.4
Density Functional Theory (DFT) and Electron Paramagnetic Resonance (EPR) spectroscopy. The data obtained support a pre‐catalyst activation step that gives access to an η2‐coordinated alkene FeI complex, followed by oxidative addition of the alkene to give an FeIII intermediate, which then undergoes reductive elimination to allow release of the isomerization product.
据报道,铁催化的烯烃异构化使用铁(II) β-二酮亚胺预催化剂。该反应在催化量的氢化物源(例如频哪醇硼烷(HBpin)或氨硼烷(H 3 N·BH 3))下进行。已研究了与烯丙基芳烃和脂肪族烯烃的反应性。通过多种手段研究了催化机理,包括氘化研究、密度泛函理论(DFT)和电子顺磁共振(EPR)光谱。获得的数据支持预催化剂活化步骤,该步骤提供了 η 2配位烯烃 Fe I络合物,然后通过氧化加成烯烃得到 Fe III中间体,然后进行还原消除以释放异构化产物。
Markovnikov versus<i>anti</i>-Markovnikov Hydrophosphination: Divergent Reactivity Using an Iron(II) β-Diketiminate Pre-Catalyst
作者:Andrew K. King、Kimberley J. Gallagher、Mary F. Mahon、Ruth L. Webster
DOI:10.1002/chem.201702374
日期:2017.7.6
The ability to tune between different regioselectivities using a common pre-catalyst is an unusual yet highly desirable process. Here, we report the use of an iron(II) pre-catalyst that can be used to synthesize vinyl phosphines in a Markovnikov-selective manner in benzene, whereas a simple change to dichloromethane as the reaction solvent leads to the Z-selective anti-Markovnikovproduct. Preliminary
Phosphine- and Amine-Borane Dehydrocoupling Using a Three-Coordinate Iron(II) β-Diketiminate Precatalyst
作者:Nathan T. Coles、Mary F. Mahon、Ruth L. Webster
DOI:10.1021/acs.organomet.7b00326
日期:2017.6.12
Dehydrocoupling of phosphine- and amine-boranes is reported using an iron(II) β-diketiminate complex. Dehydrocoupling of amine-boranes is far more facile than the phosphine counterpart, the former proceeding at room temperature with 1 mol% iron precatalyst. This low loading is sufficient to allow in situ kinetic analysis and deuterium labeling studies to be carried out. An iron amido-borane complex
<b>Iron-Catalyzed H/D Exchange of Primary Silanes, Secondary Silanes, and Tertiary Siloxanes</b>
作者:Thomas G. Linford-Wood、Mary F. Mahon、Matthew N. Grayson、Ruth L. Webster
DOI:10.1021/acscatal.2c00224
日期:2022.3.4
catalytic hydrogen/deuterium (H/D) exchange of 1° silanes, 2° silanes, and 3° siloxanes is presented, facilitated by iron-β-diketiminato complexes (1a and 1b). Near-complete H/Dexchange is observed for a variety of aryl- and alkyl-containing hydrosilanes and hydrosiloxanes. The reaction tolerates alternative hydride source pinacolborane (HBpin), with quantitative H/Dexchange. A synthetic and density functional
Hydrophosphination of Unactivated Alkenes and Alkynes Using Iron(II): Catalysis and Mechanistic Insight
作者:Maialen Espinal-Viguri、Andrew K. King、John P. Lowe、Mary F. Mahon、Ruth L. Webster
DOI:10.1021/acscatal.6b02290
日期:2016.11.4
The catalytic addition of phosphines to alkenes and alkynes is a very attractive process that offers access to phosphines in a 100% atom-economic reaction using readily available and inexpensive materials. The products are potentially useful ligands and organocatalysts. Herein, we report the first example of intramolecular hydrophosphination of a series of nonactivated phosphinoalkenes and phosphinoalkynes