39686-51-6Relevant articles and documents
Vinyl Azides as Radical Acceptors in the Vitamin B12-Catalyzed Synthesis of Unsymmetrical Ketones
Dworakowski, Krzysztof R.,Pisarek, Sabina,Hassan, Sidra,Gryko, Dorota
supporting information, p. 9068 - 9072 (2021/11/30)
Vinyl azides are very reactive species and as such are useful building blocks, in particular, in the synthesis of N-heterocycles. They can also serve as precursors of ketones. These form in reactions of vinyl azides with nucleophiles or radicals. We have found, however, that under light irradiation vitamin B12 catalyzes the reaction of vinyl azides with electrophiles to afford unsymmetrical carbonyl compounds in decent yields. Mechanistic studies revealed that alkyl radicals are key intermediates in this transformation.
Direct Synthesis of Ketones from Methyl Esters by Nickel-Catalyzed Suzuki–Miyaura Coupling
Daneshfar, Omid,Hong, Xin,Houk, Kendall N.,Newman, Stephen G.,Xie, Pei-Pei,Zheng, Yan-Long
supporting information, p. 13476 - 13483 (2021/05/10)
The direct conversion of alkyl esters to ketones has been hindered by the sluggish reactivity of the starting materials and the susceptibility of the product towards subsequent nucleophilic attack. We have now achieved a cross-coupling approach to this transformation using nickel, a bulky N-heterocyclic carbene ligand, and alkyl organoboron coupling partners. 65 alkyl ketones bearing diverse functional groups and heterocyclic scaffolds have been synthesized with this method. Catalyst-controlled chemoselectivity is observed for C(acyl)?O bond activation of multi-functional substrates bearing other bonds prone to cleavage by Ni, including aryl ether, aryl fluoride, and N-Ph amide functional groups. Density functional theory calculations provide mechanistic support for a Ni0/NiII catalytic cycle and demonstrate how stabilizing non-covalent interactions between the bulky catalyst and substrate are critical for the reaction's success.
Nickel-catalyzed Suzuki Coupling of Cycloalkyl Silyl Peroxides with Boronic Acids
Chen, Lei,Duan, Xin-Hua,Guo, Li-Na,Xu, Pengfei,Yang, Jun-Cheng,Zhang, Jun-Jie
supporting information, p. 7515 - 7525 (2020/06/27)
A nickel-catalyzed Suzuki alkyl-aryl coupling of cycloalkyl silyl peroxides with boronic acids is reported. The primary and secondary ketoalkyl electrophiles generated through C-C bond cleavage were amenable, providing rapid access to a variety of distal arylated alkyl ketones. A radical pathway is proposed for this reaction.
