Highly enantio- and diastereoselective reactions of γ-substituted butenolides through direct vinylogous conjugate additions

• Main Authors: Zhang, Wen, Tan, Davin, Lee, Richmond, Tong, Guanghu, Chen, Wenchao, Qi, Baojian, Huang, Kuo-Wei, Tan, Choon-Hong, Jiang, Zhiyong
• Other Authors: School of Physical and Mathematical Sciences
• Format: Article
• Language: English
• Published: 2013
• Subjects: DRNTU::Science::Chemistry
• Online Access: https://hdl.handle.net/10356/98442; http://hdl.handle.net/10220/12455
• Institution: Nanyang Technological University

The strength of the weak: An L-tert-leucine-derived amine–thiourea catalyst (see scheme, green box) promotes the asymmetric vinylogous conjugate addition reaction between γ-aryl- and alkyl-substituted butenolides with the butenamides and enoates shown. Computational studies show the preference for the observed stereochemistry is a result of favourable weak non-bonding interactions, which stabilize the transition state.