Department of Chemistry, University of Texas at San Antonio , One UTSA Circle, San Antonio, Texas 78249-0698, United States.
J Org Chem. 2013 Nov 1;78(21):10947-53. doi: 10.1021/jo4019304. Epub 2013 Oct 24.
The List-Barbas-Mannich reaction of ethyl (p-methoxyphenylimino)acetate (p-methoxyphenyl = PMP) with unmodified aldehydes or ketones catalyzed by modularly designed organocatalysts (MDOs) that are self-assembled from proline and cinchona alkaloid thioureas (such as a quinidine-derived thiourea) produces the corresponding γ-oxo-α-amino acid derivatives in high yields and excellent stereoselectivities. No solvent is necessary for this reaction. Aldehydes are especially good substrates for this reaction: The reaction takes only a few minutes to yield the corresponding List-Barbas-Mannich products in excellent dr (up to >99:1) and ee values (up to >99% ee).
(p-甲氧基苯基亚氨基)乙酸乙酯(p-甲氧基苯基=PMP)与未经修饰的醛或酮的 List-Barbas-Mannich 反应,在由脯氨酸和金鸡纳生物碱硫脲(如奎宁衍生的硫脲)自组装而成的模块化设计的有机催化剂(MDOs)的催化下,可以高产率和优异的立体选择性得到相应的γ-氧代-α-氨基酸衍生物。此反应不需要溶剂。醛是此反应的特别好的底物:反应只需几分钟即可得到相应的 List-Barbas-Mannich 产物,dr(高达>99:1)和 ee 值(高达>99%ee)非常优异。