253426-69-6Relevant articles and documents
Carbonylative C?C Bond Activation of Electron-Poor Cyclopropanes: Rhodium-Catalyzed (3+1+2) Cycloadditions of Cyclopropylamides
Dalling, Andrew G.,Yamauchi, Takayuki,McCreanor, Niall G.,Cox, Lydia,Bower, John F.
supporting information, p. 221 - 225 (2018/12/11)
Rh-catalyzed carbonylative C?C bond activation of cyclopropylamides generates configurationally stable rhodacyclopentanones that engage tethered alkenes in (3+1+2) cycloadditions. These studies provide the first examples of multicomponent cycloadditions t
Asymmetric Aminalization via Cation-Binding Catalysis
Park, Sang Yeon,Liu, Yidong,Oh, Joong Suk,Kweon, Yoo Kyung,Jeong, Yong Bok,Duan, Mengying,Tan, Yu,Lee, Ji-Woong,Yan, Hailong,Song, Choong Eui
supporting information, p. 1020 - 1025 (2017/12/15)
Asymmetric cation-binding catalysis, in principle, can generate “chiral” anionic nucleophiles, where the counter cations are coordinated within chiral environments. Nitrogen nucleophiles are intrinsically basic, therefore, its use as nucleophiles is often challenging and limiting the scope of the reaction. Particularly, a formation of configurationally labile aminal centers with alkyl substituents has been a formidable challenge due to the enamine/imine equilibrium of electrophilic substrates. Herein, we report enantioselective nucleophilic addition reactions of potassium phthalimides to Boc-protected alkyl- and aryl-substituted α-amido sulfones. In situ generated imines smoothly reacted with the nitrogen nucleophiles to corresponding aminals with good to excellent enantioselectivitiy under mild reaction conditions. In addition, transformation of aminal products gave biologically relevant pyrrolidinone-fused hexahydropyrimidine scaffold with excellent stereoselectivity and good yield.
A new family of cinchona-derived bifunctional asymmetric phase-transfer catalysts: Application to the enantio- and diastereoselective nitro-Mannich reaction of amidosulfones
Johnson, Kayli M.,Rattley, Matt S.,Sladojevich, Filippo,Barber, David M.,Nunez, Marta G.,Goldys, Anna M.,Dixon, Darren J.
supporting information; body text, p. 2492 - 2495 (2012/08/28)
A new family of bifunctional H-bond donor phase-transfer catalysts derived from cinchona alkaloids has been developed and evaluated in the enantio- and diastereoselective nitro-Mannich reaction of in situ generated N-Boc-protected imines of aliphatic, aromatic, and heteroaromatic aldehydes. Under optimal conditions, good reactivity and high diastereoselectivities (up to 24:1 dr) and enantioselectivities (up to 95% ee) were obtained using a 9-amino-9- deoxyepiquinidine-derived phase-transfer catalyst possessing a 3,5-bis(trifluoromethyl)phenylurea H-bond donor group at the 9-position.
