144945-22-2Relevant academic research and scientific papers
Asymmetric Synthesis of α-Quaternary γ-Lactams through Palladium-Catalyzed Asymmetric Allylic Alkylation
Song, Tao,Arseniyadis, Stellios,Cossy, Janine
supporting information, p. 603 - 607 (2019/02/28)
The synthesis of chiral unsaturated γ-lactams is reported featuring a highly enantioselective palladium-catalyzed asymmetric allylic alkylation of α, γ-disubstituted 2-silyloxypyrroles. This method allows a straightforward access to optically active γ-lactams bearing an α-quaternary stereogenic center in high yields (up to 93%), high regioselectivities (up to >20:1), and excellent enantioselectivities (up to 95% ee). To further demonstrate the synthetic utility of the method, the resulting allylated products were converted to various versatile chiral building blocks, such as pyrrolidines and pyrrolidinones.
Sc-catalyzed aldol-yype additions of N-Benzoylcyclopropanecarboxamides via iodide-mediated ring-opening: Stereoselective synthes of □-Lactams
Wiedemann, Sean H.,Noda, Hidetoshi,Harada, Shinji,Matsunaga, Shigeki,Shibasaki, Masakatsu
supporting information; experimental part, p. 1661 - 1664 (2009/04/10)
A new catalytic aldol-type addition of cyclopropanecarboximides to aldehydes via iodide-mediated ring-opening is presented. The reaction was found to be catalyzed at 0 °C using either a Sc(OTf)3/Nal system or Scl3. Stereoselective formation of αα-disubstituted enolates occurred in situ. γ-Lactams bearing α-carbonyl quaternary stereocenters were obtained in 97-57% yield and dr = 90:10-80:20 after ring closure.
