Enantioselective synthesis of trans-dihydrobenzofurans via primary amine-thiourea organocatalyzed intramolecular Michael addition.
A primary amine-thiourea organocatalyzed intramolecular Michael addition access was developed for the synthesis of trans-dihydrobenzofurans. Under the catalysis of an (R,R)-1,2-diphenylethylamine derived primary amine-thiourea bearing a glucosyl scaffold, the corresponding trans-dihydrobenzofurans were obtained in high yields with excellent level of enantioselectivities (94 to >99% ee). Moreover, an in situ isomerization occurring at high temperature gave good to excellent trans/cis ratios as well (trans/cis: 84/16-96/4).
State Key Laboratory of Elemento-Organic Chemistry, Institute of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, PR China.
Aidang
A
Lu
Keling
K
Hu
Youming
Y
Wang
Haibin
H
Song
Zhenghong
Z
Zhou
Jianxin
J
Fang
Chuchi
C
Tang
D000588:Amines / Q000737:chemistry*; D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D013237:Stereoisomerism; D013890:Thiourea / Q000737:chemistry*
D000588:Amines; D001572:Benzofurans; D013890:Thiourea