An Improved and Stereoselective Route to All-cis-2,6-Disubstituted 4-Hydroxypiperidines from Accessible 4-Substituted 4-N-Benzylaminobut-1-enes
作者:Alexey Varlamov、Vladimir Kouznetsov、Fedor Zubkov、Alexey Chernyshev、Olga Shurupova、Leonor Y. Vargas Méndez、Alirio Palma Rodríguez、Juliette Rivero Castro、Alfredo J. Rosas-Romero
DOI:10.1055/s-2002-25770
日期:——
The reaction between allylmagnesium bromide and imines 5a-l leads to the corresponding 4-substituted 4- N-benzy- laminobut-1-enes 6a-l, which were oxidized in a regioselective manner to the alkenylnitrones 7a-l. The intramolecular 1,3-dipolar cycloaddition of these nitrones gave 2-spiroannulated or 2-substi- tuted 6-exo-phenyl-1-aza-7-oxabicyclo(2.2.1)heptanes 8a-j. Re- ductive cleavage of the N-O