Palladium Complexes with Aqueous-Partitioning Dibenzylideneacetone Ligands. A New Strategy for Catalyst Design in Suzuki Polycondensation Reactions

Jennifer W. Eddy; Evan A. Davey; Richard D. Malsom; Andrew R. Ehle; Scott Kassel; Felix E. Goodson

doi:10.1021/ma901793g

Palladium Complexes with Aqueous-Partitioning Dibenzylideneacetone Ligands. A New Strategy for Catalyst Design in Suzuki Polycondensation Reactions

Macromolecules ◽

10.1021/ma901793g ◽

2009 ◽

Vol 42 (22) ◽

pp. 8611-8614 ◽

Cited By ~ 6

Author(s):

Jennifer W. Eddy ◽

Evan A. Davey ◽

Richard D. Malsom ◽

Andrew R. Ehle ◽

Scott Kassel ◽

...

Keyword(s):

Palladium Complexes ◽

Catalyst Design ◽

Suzuki Polycondensation ◽

New Strategy

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Catalysts for Suzuki Polycondensation: Ionic and “Quasi-Ionic” Amphipathic Palladium Complexes with Self-Phase-Transfer Features

Chemistry - A European Journal ◽

10.1002/chem.201202162 ◽

2012 ◽

Vol 18 (44) ◽

pp. 13941-13944 ◽

Cited By ~ 9

Author(s):

Jing Li ◽

Hongwei Fu ◽

Pan Hu ◽

Zilong Zhang ◽

Xiao Li ◽

...

Keyword(s):

Phase Transfer ◽

Palladium Complexes ◽

Suzuki Polycondensation

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Palladium-catalyzed allene synthesis enabled by β-hydrogen elimination from sp2-carbon

10.21203/rs.3.rs-49143/v1 ◽

2020 ◽

Author(s):

Ge Zhang ◽

Yi-Kang Song ◽

Fang Zhang ◽

Ze-Jian Xue ◽

Meng-Yao Li ◽

...

Keyword(s):

Reaction Mechanism ◽

Rational Design ◽

Deep Understanding ◽

Palladium Complexes ◽

Diazo Compounds ◽

Hydrogen Elimination ◽

New Strategy ◽

Palladium Catalyzed ◽

Diazo Carbonyl Compounds ◽

Viable Approach

Abstract The rational design based on a deep understanding of the present reaction mechanism is an important, viable approach to discover new organic transformations. β-Hydrogen elimination from palladium complexes is an fundamental reaction in palladium catalysis. Normally, the eliminated β-hydrogen has to be attached to a sp3-carbon. We envision that the hydrogen elimination from sp2-carbon is possible by using delicately planed reaction systems, which may offer a new strategy for the preparation of allenes. With this consideration in mind, the palladium-catalyzed cross-coupling of 2,2-diarylvinyl bromides with diazo compounds was realized with a β-vinylic hydrogen elimination from allylic palladium intermediate as the key step. Both aryl diazo carbonyl compounds and N-tosylhydrazones are competent carbene precursors in this reaction. The reaction mechanism was explored by control experiments, KIE studies and DFT calculations

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Aerobic Alcohol Oxidation with Cationic Palladium Complexes: Insights into Catalyst Design and Decomposition

Organometallics ◽

10.1021/om700492n ◽

2007 ◽

Vol 26 (23) ◽

pp. 5447-5453 ◽

Cited By ~ 76

Author(s):

Nicholas R. Conley ◽

Liezel A. Labios ◽

David M. Pearson ◽

Charles C. L. McCrory ◽

Robert M. Waymouth

Keyword(s):

Alcohol Oxidation ◽

Palladium Complexes ◽

Catalyst Design ◽

Cationic Palladium

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1,3-Diene Polymerization Mediated by Homoleptic Tetramethylaluminates of the Rare-Earth Metals

Catalysts ◽

10.3390/catal8020061 ◽

2018 ◽

Vol 8 (2) ◽

pp. 61 ◽

Cited By ~ 7

Author(s):

◽

...

Keyword(s):

Rare Earth ◽

Rare Earth Metals ◽

Active Species ◽

Catalyst Design ◽

Efficient Catalyst ◽

Co Catalysts ◽

Useful Components ◽

Polymerization Behavior ◽

New Strategy ◽

Trivalent Rare Earth

During the past two decades homoleptic tetramethylaluminates of the trivalent rare-earth metals, Ln(AlMe4)3, have emerged as useful components for efficient catalyst design in the field of 1,3-diene polymerization. Previous work had focused on isoprene polymerization applying Ln(AlMe4)3 precatalysts with Ln = La, Ce, Pr, Nd, Gd and Y, in the presence of Et2AlCl as an activator. Polymerizations employing Ln(AlMe4)3 with Ln = La, Y and Nd along with borate/borane co-catalysts [Ph3C][B(C6F5)4], [PhNMe2H][B(C6F5)4] and [B(C6F5)3] were mainly investigated for reasons of comparison with ancillary ligand-supported systems (cf. half-sandwich complexes). The present study investigates into a total of eleven rare-earth elements, namely Ln = La, Ce, Pr, Nd, Gd, Tb, Dy, Ho, Y, Er and Lu. A full overview on the polymerization behavior of Ln(AlMe4)3 in the presence of perfluorinated borate/borane cocatalysts and R2AlCl-type activators (R = Me, Et) is provided, probing the monomers isoprene and 1,3-butadiene (and preliminary ethylene). Virtually complete cis-1,4-selectivities are obtained for several catalyst/cocatalyst combinations (e.g., Gd(AlMe4)3/Me2AlCl, >99.9%). Insights into the ‘black box’ of active species are obtained by indirect observations via screening of pre-reaction time and cocatalyst concentration. The microstructure of the polydienes is investigated by combined 1H/13C NMR and ATR-IR spectroscopies. Furthermore, the reaction of [LuMe6(Li(thf)x)3] with AlMe3 has been applied as a new strategy for the efficient synthesis of Lu(AlMe4)3. The solid-state structures of Gd(AlMe4)3 and Tb(AlMe4)3 are reported.

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Palladium-catalyzed allene synthesis enabled by β-hydrogen elimination from sp2-carbon

Nature Communications ◽

10.1038/s41467-020-20740-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Ge Zhang ◽

Yi-Kang Song ◽

Fang Zhang ◽

Ze-Jian Xue ◽

Meng-Yao Li ◽

...

Keyword(s):

Reaction Mechanism ◽

Rational Design ◽

Deep Understanding ◽

Palladium Complexes ◽

Diazo Compounds ◽

Hydrogen Elimination ◽

New Strategy ◽

Palladium Catalyzed ◽

Diazo Carbonyl Compounds ◽

Viable Approach

AbstractThe rational design based on a deep understanding of the present reaction mechanism is an important, viable approach to discover new organic transformations. β-Hydrogen elimination from palladium complexes is a fundamental reaction in palladium catalysis. Normally, the eliminated β-hydrogen has to be attached to a sp3-carbon. We envision that the hydrogen elimination from sp2-carbon is possible by using thoroughly designed reaction systems, which may offer a new strategy for the preparation of allenes. Here, we describe a palladium-catalyzed cross-coupling of 2,2-diarylvinyl bromides and diazo compounds, where a β-vinylic hydrogen elimination from allylic palladium intermediate is proposed to be the key step. Both aryl diazo carbonyl compounds and N-tosylhydrazones are competent carbene precursors in this reaction. The reaction mechanism is explored by control experiments, KIE studies and DFT calculations.

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