Tag

Organic Synthesis

All articles tagged with #organic synthesis

science9 days ago•26 min saved

New Ligand Design Enables Low-Loading Nickel Catalysis for Broad C-Heteroatom Couplings

Researchers have developed a new nickel-catalyzed method for forming carbon-heteroatom bonds using visible light and a novel ligand, enabling reactions with electron-rich aryl bromides at catalyst loadings as low as 100 ppm. This approach overcomes previous limitations in oxidative addition reactivity and allows for the coupling of sterically hindered nucleophiles, including tertiary alcohols, without requiring substrate-specific optimization. The method supports gram-scale synthesis and late-stage functionalization of complex pharmaceutical molecules, offering a more efficient alternative to traditional palladium catalysis.

via Nature|

#ligand-design #nickel-catalysis #organic-synthesis

science14 days ago•9 min saved

Biocatalytic Breakthrough Enables Direct Synthesis of Chiral Oxazolidinones from Simple Alkenes

Researchers at Caltech and the University of Pittsburgh have developed a new biocatalytic method to synthesize chiral oxazolidinones, key scaffolds in next-generation antibiotics, directly from unactivated alkenes using engineered haemproteins.

via Nature|

#antibiotics #biocatalysis #directed-evolution

science1 month ago•10 min saved

Stereochemistry-Smart Ketone Editing via Pd(II)/Pd(IV) Decarboxylative Rearrangement

A Nature study reveals a palladium(II)/Pd(IV)–catalyzed decarboxylative semi-pinacol rearrangement that converts β-hydroxy carboxylic acids into ketones through a concerted six-membered Pd(IV) chelate, enabling precise stereochemical control (migrating carbon preserves configuration while the α-carbon inverts) and high migrating-group selectivity for unsymmetrical ketones. The method applies broadly to cyclic and acyclic ketones and aldehydes, avoids hazardous diazo reagents, and is showcased in a concise total synthesis of rupestine D, highlighting its potential as a versatile carbon-skeleton-editing tool.

via Nature|

#decarboxylative-rearrangement #organic-synthesis #palladium-catalysis

science2 months ago•23 min saved

Dichloromethane unlocks metal-free amide formation

Korean researchers report that dichloromethane (DCM) can act as an amide-coupling reagent, enabling amide bond formation between carboxylic acids and alkyl amines using a basic salt, without metal catalysts, and scalable to more than 20 g per batch. While the method often preserves stereochemistry, it struggles with bulky or aromatic amines, and DCM’s health hazards pose potential industrial hurdles. Nevertheless, the inexpensive, simple protocol could offer a practical alternative to harsher, toxic reagents in suitable cases.

via Chemical & Engineering News|

#amide-coupling #amines #carboxylic-acid

science4 months ago•24 min saved

Radical cross-coupling preserves stereochemistry, enabling new chiral building blocks

Baran and coworkers report a nickel-catalyzed alkyl-alkyl cross-coupling that forms a C–C bond between a chiral sulfonylhydrazide radical and an alkyl halide without racemizing the stereocenter, achieved via a diazene-cage mechanism. This unusual radical process preserves enantioenrichment in the product, enabling direct access to chiral motifs like piperidines and pyrrolidines without chiral ligands or directing groups, though the method currently works best with cyclic sulfonylhydrazides and requires further scope expansion.

via Chemical & Engineering News|

#chemistry #nickel-catalysis #organic-synthesis

chemistry3 years ago•14 min saved

Revolutionizing Cross-Coupling: Geminal-Atom Catalysis Unleashed

Researchers have developed geminal-atom catalysis, a new approach for cross-coupling reactions in organic synthesis. This method bridges the gap between homogeneous and heterogeneous catalysis by utilizing heterogeneous single-metal-site catalysts. Geminal-atom catalysis offers potential advantages such as improved selectivity, recyclability, and scalability, making it a promising tool for sustainable organic synthesis. The data for this study are available in the manuscript and supplementary information, as well as in the Zenodo repository.

via Nature.com|

#chemistry #cross-coupling #geminal-atom-catalysis

chemistry3 years ago•3 min saved

Isomer of Benzene gains prominence in organic synthesis.

Researchers have demonstrated that the high energy compound 1,2,3-cyclohexatriene, an overlooked isomer of benzene, can participate in a diverse range of cycloaddition, nucleophilic addition, and σ-bond insertion reactions, enabling chemists to construct complex molecular architectures in just a few steps. The team hopes that its work inspires others to explore and exploit the synthetic potential of these high-energy reagents going forwards.

via Chemistry World|

#benzene-isomers #chemistry #cycloaddition