893738-91-5Relevant academic research and scientific papers
Formation of a carbonyl group ortho to a biaryl structure or a 6H-dibenzopyran by a palladium/norbornene-catalyzed ordered reaction sequence
Della Ca, Nicola,Fontana, Marco,Xu, Di,Cremaschi, Mirko,Lucentini, Riccardo,Zhou, Zhi-Ming,Catellani, Marta,Motti, Elena
, p. 6389 - 6401 (2015/08/18)
Abstract Developments are reported in the catalytic synthesis of biaryls containing an ortho-carbaldehyde or 6H-dibenzopyrans in the presence of palladium/norbornene as catalyst. The reaction of o-substituted aryl iodides and o-bromobenzyl alcohols proceeds by unsymmetrical aryl-aryl coupling to form a seven-membered oxapalladacycle intermediate, which may undergo an intramolecular redox process to form carbonyl groups or a C-O coupling to six-membered cyclic ethers. The predominant formation of dibenzopyrans as well as of biaryl structures containing the oxidized CHO group in one ring and the reduced CH2OH in the other is described along with some mechanistic insights.
Development of unimolecular tetrakis(piperidin-4-ol) as a ligand for Suzuki-Miyaura cross-coupling reactions: Synthesis of incrustoporin and preclamol
Nallasivam, Jothi L.,Fernandes, Rodney A.
, p. 3558 - 3567 (2015/06/08)
Abstract A domino aza-Cope/aza-Prins cascade enabled the synthesis of a new class of 4-hydroxypiperidine-appended mono, bis, tris, and tetrakis unimolecular compounds that served as efficient ligands to catalyze Suzuki-Miyaura cross-coupling reactions under aerobic conditions. Various biaryls, terphenyls, and heterocyclic biphenyls were obtained in good to excellent yields. The ligands were also capable of catalyzing the Heck-Mizoroki reaction. As an application, the Suzuki-Miyaura coupling reaction was used in the synthesis of incrustoporin, its analogs, and the drug molecule preclamol. A domino aza-Cope/aza-Prins cascade enabled the synthesis of a new class of 4-hydroxypiperidine-appended mono-, bis-, tris-, and tetrakis-unimolecular compounds that served as efficient ligands to catalyze Suzuki-Miyaura cross-coupling reactions under aerobic conditions. Various biaryls, terphenyls, and heterocyclic biphenyls were obtained in good to excellent yields.
