1363415-72-8Relevant academic research and scientific papers
Palladium/NHC (NHC = N-Heterocyclic Carbene)-Catalyzed B-Alkyl Suzuki Cross-Coupling of Amides by Selective N-C Bond Cleavage
Meng, Guangrong,Szostak, Michal
, p. 6789 - 6793 (2018)
A highly chemoselective, palladium-NHC (NHC = N-heterocyclic carbene)-catalyzed, direct cross-coupling between B-sp3-alkyl reagents and activated amides by N-C(O) cleavage is reported. Palladium-NHC precatalysts promote chemoselective alkylations of amides that are inaccessible by applying strong organometallic reagents. Various amides, including challenging primary amides after direct and site-selective N,N-di-Boc activation, are compatible with this method. The potential of this mild protocol is demonstrated in sequential C(sp2)-C(sp2)/C(sp2)-C(sp3) cross-couplings deploying a di-Boc amide derived from a common primary amide bond. The method provides a rare example of air- and moisture-stable, well-defined, and highly reactive Pd-NHC precatalysts in B-alkyl-Suzuki cross-couplings.
Chemoselective synthesis of ketones and ketimines by addition of organometallic reagents to secondary amides
Bechara, William S.,Pelletier, Guillaume,Charette, Andre B.
experimental part, p. 228 - 234 (2012/06/01)
The development of efficient and selective transformations is crucial in synthetic chemistry as it opens new possibilities in the total synthesis of complex molecules. Applying such reactions to the synthesis of ketones is of great importance, as this motif serves as a synthetic handle for the elaboration of numerous organic functionalities. In this context, we report a general and chemoselective method based on an activation/addition sequence on secondary amides allowing the controlled isolation of structurally diverse ketones and ketimines. The generation of a highly electrophilic imidoyl triflate intermediate was found to be pivotal in the observed exceptional functional group tolerance, allowing the facile addition of readily available Grignard and diorganozinc reagents to amides, and avoiding commonly observed over-addition or reduction side reactions. The methodology has been applied to the formal synthesis of analogues of the antineoplastic agent Bexarotene and to the rapid and efficient synthesis of unsymmetrical diketones in a one-pot procedure. Macmillan Publishers Limited. All rights reserved.
