Chiral Phosphoric Acid Catalyzed Enantioselective [4 + 2] Cycloaddition Reaction of α-Fluorostyrenes with Imines
作者:Jun Kikuchi、Haiting Ye、Masahiro Terada
DOI:10.1021/acs.orglett.0c03360
日期:2020.11.20
An enantioselective [4 + 2] cycloaddition reaction of α-fluorostyrenes with N-benzoyl imines was demonstrated using a chiral phosphoric acid catalyst. Cycloaddition products having fluorine functionality were formed in high yields with excellent diastereo- and enantioselectivities. Further manipulation of the enantioenriched cycloaddition product with silyl enol ether in the presence of BiCl3 catalyst
使用手性磷酸催化剂证明了α-氟苯乙烯与N-苯甲酰基亚胺的对映选择性[4 + 2]环加成反应。具有氟官能团的环加成产物以高收率形成,具有优异的非对映选择性和对映选择性。在BiCl 3催化剂存在下,用甲硅烷基烯醇醚进一步处理对映体富集的环加成产物,得到的取代产物可通过选择性碳-氟键裂解保留二氢-4 H -1,3-恶嗪骨架,而不会损失对映体过量。