Wang Qingqing, Wang Wei, Ye Ling, Yang Xuejun, Li Xinying, Zhao Zhigang, Li Xuefeng
College of Chemistry and Environment Protection Engineering, Southwest Minzu University, Chengdu 610041, China.
Faculty of Geosciences and Environmental Engineering, Southwest Jiaotong University, Chengdu 610031, China.
Molecules. 2017 Jun 30;22(7):1096. doi: 10.3390/molecules22071096.
An enantioselective (52-98% ee) Michael addition between cyclic β-diones and α,β-unsaturated enones was established in the presence of quinine-based primary amine or squaramide. A variety of cinnamones were smoothly converted into the desired 3,4-dihydropyrans in moderate to high yields (63-99%). Chalcones were also suitable acceptors and gave rise to the expected adducts in satisfactory yields (31-99%). The resulting adducts readily underwent further modification to form fused 4H-pyran or 2,3-dihydrofuran.
在基于奎宁的伯胺或方酰胺存在下，实现了环状β-二酮与α,β-不饱和烯酮之间的对映选择性迈克尔加成反应（对映体过量值为52 - 98%）。多种肉桂酮能顺利转化为所需的3,4-二氢吡喃，产率适中至高（63 - 99%）。查耳酮也是合适的受体，并以令人满意的产率（31 - 99%）生成预期的加合物。所得加合物易于进一步修饰，形成稠合的4H-吡喃或2,3-二氢呋喃。
