470676-68-7Relevant academic research and scientific papers
Highly Enantioselective Iridium-Catalyzed Hydrogenation of Conjugated Trisubstituted Enones
Peters, Bram B. C.,Jongcharoenkamol, Jira,Krajangsri, Suppachai,Andersson, Pher G.
, p. 242 - 246 (2021/01/13)
Asymmetric hydrogenation of conjugated enones is one of the most efficient and straightforward methods to prepare optically active ketones. In this study, chiral bidentate Ir-N,P complexes were utilized to access these scaffolds for ketones bearing the stereogenic center at both the α- and β-positions. Excellent enantiomeric excesses, of up to 99%, were obtained, accompanied with good to high isolated yields. Challenging dialkyl substituted substrates, which are difficult to hydrogenate with satisfactory chiral induction, were hydrogenated in a highly enantioselective fashion.
A new approach to the Nazarov reaction via sequential electrocyclic ring opening and ring closure
Grant, Tina N.,West
, p. 9348 - 9349 (2007/10/03)
Regioselective dichlorocyclopropanation of 2-silyloxydienes furnishes vinylcyclopropanol silyl ethers in good yield. Treatment with silver(I) at room temperature effects disrotatory electrocyclic opening to a 2-chloro-3-silyloxypentadienyl cation, which then undergoes conrotatory (Nazarov) electrocyclization to provide chlorocyclopentenones. This two-step sequence offers a convenient and mild alternative to the standard Nazarov cyclization protocol via a formal 4+1 construction and furnishes products containing useful halogen functionality. In one case possessing a pendant phenyl group, interrupted Nazarov reaction to give a benzohydrindenone was observed. Copyright
