Unexpected E-stereoselective reductive A3-coupling reaction of terminal alkynes with aldehydes and amines.
The transition-metal catalysed three-component coupling of an alkyne, an aldehyde and an amine has been became a widely used method for preparing propargylic amines. Here, we report an unexpected copper(I)-catalysed E-stereoselective reduction of propargylic amines in situ formed from readily available terminal alkynes, aldehydes and 3-pyrroline or isoindoline via [1,5]-hydride transfer, affording E-allylic amines. Through mechanistic studies, it is believed that the unsaturated cyclic dialkylamine is acting as hydrogen donor.
Shanghai Key Laboratory of Green Chemistry and Chemical Process, Department of Chemistry, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China.
Wu
W
Fan
Shanghai Key Laboratory of Green Chemistry and Chemical Process, Department of Chemistry, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China.
Weiming
W
Yuan
1] Shanghai Key Laboratory of Green Chemistry and Chemical Process, Department of Chemistry, East China Normal University, 3663 North Zhongshan Road, Shanghai 200062, China [2] State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.
Shengming
S
Ma