1048976-74-4Relevant academic research and scientific papers
Copper-Catalyzed Cyclization/aza-Claisen Rearrangement Cascade Initiated by Ketenimine Formation: An Efficient Stereocontrolled Synthesis of α-Allyl Cyclic Amidines
Xu, Hua-Dong,Jia, Zhi-Hong,Xu, Ke,Han, Mei,Jiang, Sai-Nan,Cao, Jing,Wang, Jia-Cheng,Shen, Mei-Hua
, p. 9284 - 9288,5 (2014)
An efficient and convenient synthesis of α-allyl cyclic amidines has been achieved by applying a novel cascade reaction. Copper(I)-mediated insitu N-sulfonyl ketenimine formation from the reaction of a terminal alkyne with sulfonyl azide is followed by an intramolecular nucleophilic attack on the central carbon atom by an allylic tertiary amine, and then an aza-Claisen rearrangement takes place through a chair transition state to furnish the titled amidines with complete stereocontrol. After a pattern: A convenient copper-catalyzed method for cyclic amidine synthesis with high yield under mild reaction conditions has been established. By using this method, tertiary allyl enynes, with broad substitution patterns, can be converted stereoselectively into α-allyl cyclic amidines bearing multiple functionalities for potential elaboration. DIPEA=diisopropylethylamine.
