1604833-34-2Relevant academic research and scientific papers
Substrate-Induced Dimerization Assembly of Chiral Macrocycle Catalysts toward Cooperative Asymmetric Catalysis
Ao, Yu-Fei,Guo, Hao,Meng, Wei,Wang, De-Xian,Wang, Qi-Qiang,Zhang, Lie-Wei,Zhou, Hao
supporting information, p. 2623 - 2627 (2020/02/04)
An artificial system of substrate-induced dimerization assembly of chiral macrocycle catalysts enables a highly cooperative hydrogen-bonding activation network for efficient enantioselective transformation. These macrocycles contain two thiourea and two chiral diamine moieties and dimerize with sulfate to form a sandwich-like assembly. The macrocycles then adopt an extended conformation and reciprocally complement the hydrogen-bonding interaction sites. Inspired by the guest-induced dynamic assembly, these macrocycles catalyze the decarboxylative Mannich reaction of cyclic aldimines containing a sulfamate heading group. The imine substrate can be activated toward nucleophilic attack of β-ketoacid by a cooperative hydrogen-bonding network enabled by sulfamate-induced dimerization assembly of the macrocycle catalysts. Highly efficient (>95 % yield in most cases) and enantioselective (up to 97.5:2.5 er) transformation of a variety of substrates using only 5 mol % macrocycle was achieved.
Cyclic aldimines as superior electrophiles for Cu-catalyzed decarboxylative mannich reaction of β-ketoacids with a broad scope and high enantioselectivity
Zhang, Heng-Xia,Nie, Jing,Cai, Hua,Ma, Jun-An
supporting information, p. 2542 - 2545 (2014/05/20)
A novel Cu-catalyzed enantioselective decarboxylative Mannich reaction of cyclic aldimines with β-ketoacids is described. The cyclic structure of these aldimines, in which the C=N bond is constrained in the Z geometry, appears to be important, allowing Mannich condensation to proceed in high yields with excellent enantioselectivities. A chiral chroman-4-amine was synthesized from the decarboxylative Mannich product in several steps without loss of enantioselectivity.
