Novel thiophosphonodiamides as efficient hydrogen bond donor catalysts in tandem Michael additionecyclization of malononitrile and 2-(E)-2-nitrovinylphenols
writer：Keling Hu, Youming Wang, Zhenghong Zhou*, Chuchi Tang
keywords：thiophosphonodiamides, hydrogen bond donor catalysts
source：期刊
specific source：Tetrahedron
Issue time：2014年
From L-amino acid, three chiral thiophosphonodiamides were prepared as new hydrogen bond donor organocatalysts. Under the mediation of the catalyst derived from L-valine, a tandem Michael addition/ cyclization reaction between (E)-2-(2-nitrovinyl)phenols and malononitrile proceeds smoothly, giving pharmaceutically valuable 2-amino-4H-chromene-3-carbonitriles in high yields with 66-95% ee within 2 h.