949119-70-4Relevant academic research and scientific papers
Improved access to chiral tetranaphthoazepinium-based organocatalysts using aqueous ammonia as nitrogen source
Manaprasertsak, Auraya,Tharamak, Sorachat,Schedl, Christina,Roller, Alexander,Widhalm, Michael
supporting information, (2019/11/05)
The class of 3,30-diaryl substituted tetranaphthobisazepinium bromides has found wide application as highly efficient C2-symmetrical phase-transfer catalysts (PTCs, Maruoka type catalysts). Unfortunately, the synthesis requires a lar
Dimeric cinchona ammonium salts with benzophenone linkers: Enantioselective phase transfer catalysts for the synthesis of α-Amino acids
Woo, Seunga,Kim, Yong-Gyun,Lim, Baegeun,Oh, Jiin,Lee, Yeonji,Gwon, Hyeri,Nahm, Keepyung
, p. 2157 - 2160 (2018/02/06)
Chiral phase transfer catalysts of dimeric cinchona ammonium salts linked with a benzophenone bridge showed high enantioselectivity in the α-Alkylation of a glycinate ester under mild industry-Applicable conditions: 0.5 mol% PTC and near equivalents of al
Pd/Cu dual catalysis: Highly enantioselective access to α-substituted α-amino acids and α-amino amides
Huo, Xiaohong,Fu, Jingke,He, Xiaobo,Chen, Jianzhong,Xie, Fang,Zhang, Wanbin
supporting information, p. 599 - 602 (2018/02/06)
The asymmetric allylation of glycine iminoesters has been accomplished through a synergistic Pd/Cu catalyst system, affording a range of α-substituted α-amino acids in high yields and with excellent enantioselectivities (88 → 99% ee). The introduction of a Cu-P,N-metallocenyl complex-activated glycine iminoester to the chiral palladium-catalyzed allylic allylation process is crucial owing to its high reactivity and excellent enantioselectivities. Importantly, this Pd/Cu dual catalysis strategy can be used for the asymmetric allylic alkylation of prochiral glycine amide derivatives, which could be further utilized to synthesize biologically important vicinal diamines.
Orthopalladated complexes as phase-transfer catalysts for asymmetric alkylation of achiral Schiff base esters
Kim, Dae Hyun,Im, Jin Kyu,Kim, Dae Won,Lee, Hyunjoo,Kim, Honggan,Kim, Hoon Sik,Cheong, Minserk,Mukherjee, Deb Kumar
experimental part, p. 949 - 957 (2012/01/13)
The asymmetric C-alkylation of benzophenone Schiff base glycine esters has been achieved using a palladium(II) chiral complex as a phase-transfer catalyst. The aromatic moiety around the metal center and various physicochemical parameters were investigated to study their effect on the asymmetric alkylation reaction under phase-transfer conditions. Moderate enantioselectivity(30-40%) was achieved under room temperature conditions, which is a significant improvement compared to no enantioselectivity with a chiral palladium-salen complex reported earlier. Computer simulation studies indicate that coordination of the metal center with Z-enolate forming a square planar complex provides a favorable steric environment where the α-carbon atom of the enolate is available for enantioselective alkylation.
