21327-72-0Relevant articles and documents
A Fast and General Route to Ketones from Amides and Organolithium Compounds under Aerobic Conditions: Synthetic and Mechanistic Aspects
Ghinato, Simone,Territo, Davide,Maranzana, Andrea,Capriati, Vito,Blangetti, Marco,Prandi, Cristina
, p. 2868 - 2874 (2021/01/21)
We report that the nucleophilic acyl substitution reaction of aliphatic and (hetero)aromatic amides by organolithium reagents proceeds quickly (20 s reaction time), efficiently, and chemoselectively with a broad substrate scope in the environmentally responsible cyclopentyl methyl ether, at ambient temperature and under air, to provide ketones in up to 93 % yield with an effective suppression of the notorious over-addition reaction. Detailed DFT calculations and NMR investigations support the experimental results. The described methodology was proven to be amenable to scale-up and recyclability protocols. Contrasting classical procedures carried out under inert atmospheres, this work lays the foundation for a profound paradigm shift of the reactivity of carboxylic acid amides with organolithiums, with ketones being straightforwardly obtained by simply combining the reagents under aerobic conditions and with no need of using previously modified or pre-activated amides, as recommended.
HMPA-catalyzed transfer hydrogenation of 3-carbonyl pyridines and other N-heteroarenes with trichlorosilane
Fu, Yun,Sun, Jian
supporting information, (2019/02/06)
A method for the HMPA (hexamethylphosphoric triamide)-catalyzed metal-freetransfer hydrogenation of pyridines has been developed. The functional group tolerance of the existing reaction conditions provides easy access to various piperidines with ester or ketone groups at the C-3 site. The suitability of this method for the reduction of other N-heteroarenes has also been demonstrated. Thirty-three examples of different substrates have been reduced to designed products with 45–96% yields.
Synthesis of bis(heteroaryl) ketones by removal of benzylic CHR and CO groups
Maji, Arun,Rana, Sujoy,Akanksha,Maiti, Debabrata
supporting information, p. 2428 - 2432 (2014/03/21)
A copper-catalyzed method for synthesis of diaryl ketones (Ar-CO-Ar′) through removal of benzylic -CH2-, -CO-, and -CHR- groups from Ar-CO-CXR-Ar′ has been discovered. A number of symmetrical and unsymmetrical heterocyclic ketones, which are usually difficult to synthesize, can be prepared in good to excellent yields. This method was applied to the synthesis of the nonsteroidal anti-inflammatory drug suprofen (47 % yield over three steps). Based on preliminary mechanistic and kinetic studies, an active Cu/O2 species is proposed to mediate the rearrangement reaction. Snip snip: A copper-catalyzed method for synthesis of diaryl ketones by removal of benzylic CH2, CO, and CHR groups has been discovered. A number of symmetrical and unsymmetrical heterocyclic ketones, which are usually difficult to synthesize, can be prepared in good to excellent yields. Preliminary mechanistic studies indicate that an active Cu/O2 species mediates the rearrangement. Copyright
