An Organocatalytic Synthesis of Chiral Pyrano[2,3-d]pyrimidines through [3+3] Annulation of 1,3-Dimethyl-barbituric Acid with 2-(1-Alkynyl)-2-alken-1-ones

作者：Zhu, Yali; Wang, Zhonghe; Zhang, Jing; Yu, Jia; Yan, Lijuan; Li, Yang; Chen, Ligong^*; Yan, Xilong^*

来源：European Journal of Organic Chemistry, 2018, 2018(3): 347-354.

DOI：10.1002/ejoc.201701581

• Pyrimidines
• Asymmetric synthesis
• Organocatalysis
• [3+3] Annulation
• Barbituric acid

An efficient enantioselective [3+3] annulation has been developed to synthesize chiral pyrano[2,3-d]pyrimidines from 1,3-dimethyl-barbituric acid and 2-(1-alkynyl)-2-alken-1-ones. A thiourea-tertiary amine bifunctional catalyst was synthesized and applied in the construction of the framework of chiral pyrano[2,3-d]pyrimidines. The reaction proceeds smoothly on a broad range of substrates (18 examples) to produce the target products in moderate to good yields and enantioselectivities. Reduced temperature leads to an improvement of enantiomeric excesses. Steric hindrance plays an important role in the performance of the reaction.

• 出版日期2018-1-23
• 单位天津大学