Activation Strategies for Earth-Abundant Metal Catalysis

Peng, Jingying; Thomas, Stephen P.

doi:10.1055/s-0039-1690873

Cited by 8 publications

(3 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our investigation started by exploring the hydroboration of styrene ( 1a ) with pinacolborane (HBPin), using different kinds of commercially available nickel salts as the pre‐catalysts in the combination with substoichiometric amount of KO t Bu at 30°C (Table 1, entries 1—4). [ 8‐10,68 ] To our delight, Ni(DME)Cl 2 , Ni(cod) 2 and Ni(acac) 2 worked very well in the reaction, giving very high yields of the hydroboration product 2a (92%—97%) with excellent Markovnikov selectivity (> 99: 1, entries 1—3). These results suggested that the catalytic performance should be less relevant to the identities of the simple nickel precursors under 0.2 mol% loading (for details, see the Supporting Information (SI)).…”

Section: Resultsmentioning

confidence: 94%

“…also reported that the in situ formed boron ‘ate’ reductive species from the reaction between KO t Bu and HBPin can activate high‐ oxidation‐state cobalt complexes in 2017. [ 8‐10 ] Our group also disclosed that the alkoxide‐pinacolborane combination can activate CoI 2 . [ 68 ] Therefore, it is proposed that the in situ formed B‐H species from CsF and HBPin can activate the Ni(II) salt to metastable Ni NPs.…”

Section: Resultsmentioning

confidence: 99%

“…[ 1‐7 ] In addition, hazardous activators are generally required for the catalyst activation, and high catalyst loadings (1—10 mol%) are commonly needed for synthetically useful activity. [ 1‐10 ] All of these limiting factors can severely hinder the broad application of molecular catalysts in large scale organic synthesis. Therefore, the development of earth‐abundant metal catalysis with extremely high activity from commercially available metal salts, preferably by simple activation process and without the need of sophisticated ligands and/or sensitive activators, is highly desirable.…”

Section: Background and Originality Contentmentioning

confidence: 99%

See 2 more Smart Citations

Markovnikov‐Selective Hydroboration of Aryl Alkenes Enabled by a Simple Nickel Salt

Liu

Bai

et al. 2022

Chin. J. Chem.

View full text Add to dashboard Cite

Comprehensive Summary The sustainable development of synthetic reactions catalyzed by earth‐abundant metals is one of the principal goals in homogeneous catalysis. However, so far most of the protocols are still plagued by sophisticated ligands, hazardous activators, high catalyst loading (1—10 mol%) and/or multistep synthesis of the metal complexes in the process development. Consequently, the development of earth‐abundant metal catalysts with high activity from commercially available metal salts is highly desirable for practical utilization of base metal catalyzed synthetic methodology. Herein, we report the catalyst generated in situ from a mixture of catalytic amounts of Ni(acac)2 (as low as 0.005 mol%) and CsF, which is found highly active for Markovnikov‐selective hydroboration of vinylarenes, including 1,1‐disubstituted vinylarenes and internal olefins, affording a wide range of secondary and tertiary alkyl boronates in excellent yields. Mechanistic experiments indicate that the key to the success of this catalysis is the use of CsF, which in combination with pinacolborane acts as an effective activator for Ni(acac)2, probably generating metastable Ni nanoparticles in situ that demonstrate high activity in the catalytic hydroboration (TON up to 18800).

show abstract

Section: Resultsmentioning

confidence: 94%

Section: Resultsmentioning

confidence: 99%

Section: Background and Originality Contentmentioning

confidence: 99%

See 1 more Smart Citation

Markovnikov‐Selective Hydroboration of Aryl Alkenes Enabled by a Simple Nickel Salt

Liu

Bai

et al. 2022

Chin. J. Chem.

View full text Add to dashboard Cite

show abstract

Cobalt‐Catalysed, Ligand‐Controlled Regiodivergent Alkene Hydrosilylation

Docherty

Dominey²,

Thomas

2021

Asian J Org Chem

Self Cite

View full text Add to dashboard Cite

Alkene hydrosilylation is amongst the largest industrial homogenous catalysis processes. Cobalt catalysis offers a sustainable alternative to commonly used platinum catalysts to achieve this transformation. Using two bisiminopyridine cobalt(II) catalysts the regiodivergent hydrosilylation of alkenes has been developed. Variation of pre‐catalyst activator and ligand substituents were investigated to enable the controlled, regiodivergent hydrosilylation of both aryl‐ and alkyl‐substituted alkenes with phenylsilane. In contrast to other regiodivergence strategies, excellent regioselectivity for either isomer was achieved using the same ligand class but differing by a single methyl group (ethyl vs isopropyl).

show abstract

Half‐Sandwich Nickel(II) NHC‐Picolyl Complexes as Catalysts for the Hydrosilylation of Carbonyl Compounds: Evidence for NHC‐Nickel Nanoparticles under Harsh Reaction Conditions

et al. 2021

View full text Add to dashboard Cite

The cationic [NiCp(Mes‐NHC‐CH2py]Br complex 2 a was prepared directly by the reaction of nickelocene with 1‐(2‐picolyl)‐3‐mesityl‐imidazolium bromide (1), and its PF6− derivative 2 b, by subsequent salt metathesis. X‐ray diffraction studies and Variable Temperature 1H NMR experiments run with 2 a and 2 b strongly suggest the bidentate coordination of the picolyl‐functionalized carbene to the nickel both in the solid state and in solution in both cases. These data suggest the absence of hemilabile behavior of the latter, even in the presence of a coordinating anion. Both complexes show similar activity in aldehyde hydrosilylation, further implying the absence of hemilability of the picolyl‐functionalized carbene, and effectively reduce a broad scope of aldehydes in the absence of additive under mild conditions. In the case of ketones, effective hydrosilylation is only observed in the presence of a catalytic amount of potassium t‐butoxide at 100 °C. Dynamic light scattering, scanning transmission electron microscopy and X‐ray photoelectron spectroscopy show evidence for the involvement of NHC‐picolyl‐Ni nanoparticles under these conditions.

show abstract

Activation Strategies for Earth-Abundant Metal Catalysis

Cited by 8 publications

References 16 publications

Markovnikov‐Selective Hydroboration of Aryl Alkenes Enabled by a Simple Nickel Salt

Markovnikov‐Selective Hydroboration of Aryl Alkenes Enabled by a Simple Nickel Salt

Cobalt‐Catalysed, Ligand‐Controlled Regiodivergent Alkene Hydrosilylation

Half‐Sandwich Nickel(II) NHC‐Picolyl Complexes as Catalysts for the Hydrosilylation of Carbonyl Compounds: Evidence for NHC‐Nickel Nanoparticles under Harsh Reaction Conditions

Contact Info

Product

Resources

About