1,720,968 research outputs found
meta-Selective C-H Bond Alkylation with Secondary Alkyl Halides
No full textRuthenium catalysts enabled C-H bond functionalizations on arenes with challenging secondary alkyl halides. Particularly, ruthenium(II) biscarboxylate complexes proved to be the key to success for direct alkylations with excellent levels of unusual meta-selectivity. The direct alkylations occurred under mild reaction conditions with ample scope and tolerated valuable functional groups. Detailed mechanistic studies were performed, including various competition experiments as well as reactions with isotopically labeled substrates. These studies provided strong support for an initial reversible cyclometalation. The cycloruthenation thereby activates the arene for a subsequent remote electrophilic-type substitution with the secondary alkyl halides. Independently prepared cycloruthenated complexes were found to be catalytically active provided that a carboxylate ligand was present, thereby highlighting the key importance of carboxylate assistance for effective meta-selective C-H bond alkylations
Air-Stable Secondary Phosphine Oxide as Preligand for Palladium-Catalyzed Intramolecular alpha-Arylations with Chloroarenes
No full textA palladium catalyst derived from air-stable secondary phosphine oxide (1-Ad)(2)P(O)H enabled efficient intramolecular alpha-arylations of amides with aryl chlorides, which allowed for the synthesis of diversely substituted (aza)oxindoles.DFG; GIF; Alexander-von-Humboldt foundatio
ChemInform Abstract: Ruthenium-Catalyzed Oxidative Synthesis of 2-Pyridones Through C-H/N-H Bond Functionalizations.
No full textChemInform Abstract: Air‐Stable Secondary Phosphine Oxide as Preligand for Palladium‐Catalyzed Intramolecular α‐Arylations with Chloroarenes.
No full textChemInform Abstract: Ruthenium-Catalyzed Oxidative Annulation by Cleavage of C-H/N-H Bonds.
No full textChemInform Abstract: Carboxylate-Assisted Ruthenium-Catalyzed Direct Alkylations of Ketimines.
No full textRuthenium-Catalyzed Oxidative Synthesis of 2-Pyridones through C–H/N–H Bond Functionalizations
No full textAn Inexpensive ruthenium catalyst enabled oxidative annulations of alkynes by acrylamides with ample scope, which allowed for the preparation of 2-pyridones employing various electron-rich and electron-deficient acrylamides as well as (di)aryl- and (di)alkyl-substituted alkynes.DFG; CaSuS PhD progra
Carboxylate-Assisted Ruthenium-Catalyzed Direct Alkylations of Ketimines
No full textThe mechanism of carboxylate-assisted ruthenium(II)-catalyzed direct aikylations of ketimines with unactivated alkyl halides was probed through experimental studies. The remarkable chemoselectivity of the broadly applicable catalyst also enabled direct alkylations among others on H2O or under solvent-free reaction conditions.State of Lower Saxony; DF
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