title: An Arylation Strategy to Propargylamines: Catalytic Asymmetric Friedel-Crafts-type Arylation Reactions of C-Alkynyl Imines.
abstract: The first arylation strategy for the synthesis of enantioenriched propargylamines is disclosed. This approach, which is complementary to previous alkynylation and alkylation strategies, involves a C(sp2)-C(sp3) bond formation, and is based on the first asymmetric Friedel-Crafts-type arylation reaction of C-alkynyl imines. Asymmetric Friedel-Crafts reactions with electron-deficient phenols, a longstanding unsolved challenge, have thus been realized for the first time, enabled by the combination of our recently introduced C-alkynyl N-Boc-protected N,O-acetals as electrophiles and chiral phosphoric acids as catalysts. The synthetic utility of the resulting structurally diverse and polyfunctional chiral propargylamines was demonstrated by a series of selective transformations, including controlled reduction of the alkynyl group and iterative cross-couplings.
authors: Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China.
authors: Yingcheng
authors: Y
authors: Wang
authors: Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China.
authors: Liang
authors: L
authors: Jiang
authors: Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China.
authors: Long
authors: L
authors: Li
authors: Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China.
authors: Jun
authors: J
authors: Dai
authors: Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China.
authors: Dan
authors: D
authors: Xiong
authors: Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, School of Chemical Science and Technology, Yunnan University, Kunming, 650091, China.
authors: Zhihui
authors: Z
authors: Shao
keywords: Brønsted acids; Friedel-Crafts reaction; alkynyl imines; arylation; propargylamines