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Monophosphine Ligands (monophosphine + ligand)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

ChemInform Abstract: [2.2]Paracyclophane-Based Monophosphine Ligand for Palladium-Catalyzed Cross-Coupling Reactions of Aryl Chlorides.

CHEMINFORM, Issue 2 2010
Jiwu Ruan
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source]

Synthesis of Planar Chiral [2.2]Paracyclophane Monophosphine Ligands and Their Application in the Umpolung Allylation of Aldehydes.

CHEMINFORM, Issue 27 2007
Tang-Zhi Zhang
Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source]

Ferrocenyl Monophosphine Ligands: Synthesis and Applications in the Suzuki,Miyaura Coupling of Aryl Chlorides.

CHEMINFORM, Issue 12 2005
Colin Baillie
Abstract For Abstract see ChemInform Abstract in Full Text. [source]

Memory Effects in Palladium-Catalyzed Allylic Alkylations of 2-Cyclohexen-1-yl Acetate

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 17-18 2007
Nina Svensen
Abstract The objective of this work was to characterize the enantiospecificity of the allylic alkylation of enantioenriched 2-cyclohexen-1-yl acetate with the enolate ion of dimethyl malonate catalyzed by unsymmetrical palladium catalysts. The precatalysts employed were (,3 -allyl)PdLCl, where L is a monophosphine ligand [PPh3, PCy3, P(2-BiPh)Cy2, or P(t- Bu)3], all of which afforded enantiospecificity to some extent (5,47,%). Quantum mechanical calculations show that, theoretically, the enantiospecificity should be high due to a preference for the "trans to P" transition state in both formation of the ,3 -allyl intermediate and nucleophilic attack. However, the observed enantiospecificity is relatively low due to isomerization of the ,3 -allyl intermediate and/or dynamic equilibria between the catalytically active (,3 -allyl)PdLCl species and [(,3 -allyl)PdL2]+ or [(,3 -allyl)PdCl]2. It was also observed experimentally that increasing the bulk of the phosphine inhibits formation of the [(,3 -allyl)PdL2]+ complexes, significantly increasing the observed enantiospecificity for some of the ligands. [source]

Bulky Achiral Triarylphosphines Mimic BINAP in Ru(II)- Catalyzed Asymmetric Hydrogenation of Ketones

ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 9 2005
Qing Jing
Abstract In the present work, we report on catalysis of the enantioselective hydrogenation of ketones with Ru(II) complexes composed of cheap achiral monodentate phosphine ligands in combination with an enantiopure 1,2-diamine, affording a variety of optically active secondary alcohols with high efficiency and enantioselectivity. The steric impact of achiral monophosphine ligands in Ru complexes was found to be a critical factor for the high enantioselectivity of the reaction. This finding throws some light on a long-standing challenge, the high cost of chiral bisphosphine ligands, associated with an industrial application of the asymmetric hydrogenation of ketones. [source]