jo0c01446_si_001.pdf (3.86 MB)
C2‑Symmetric 1,2-Diphenylethane-1,2-diamine-Derived Primary–Tertiary Diamine-Catalyzed Asymmetric Mannich Addition of Cyclic N‑Sulfonyl Trifluoromethylated Ketimines
journal contribution
posted on 2020-08-25, 13:42 authored by Hui-Xin Duan, Yongna Zhang, Zhen-Zhen Zhang, You-Qing WangA simple
chiral primary–tertiary diamine derived from C2-symmetric 1,2-diphenylethane-1,2-diamine as
the organocatalyst in combination with the trifluoroacetic acid additive
for the asymmetric Mannich reaction of cyclic N-sulfonyl
trifluoromethylated ketimines and methyl ketones afforded the desired
product with high enantioselectivity (73–96% ee). The reactions
proceeded well for a variety of different substituted cyclic N-sulfonyl trifluoromethyl ketimines and various alkyl methyl
ketones, providing access to diverse enantioenriched benzo-fused cyclic
sulfamidate N-heterocycles bearing a trifluoromethylated
α-tetrasubstituted carbon stereocenter. This study also investigated
the diastereoselective reduction of the carbonyl group and ring cleavage
reduction of the sulfamidate group of the corresponding Mannich product.