%0 Journal Article
%A Bates, Roderick W.
%A Lu, Yongna
%D 2010
%T Synthesis of (−)-Sedinine by Allene Cyclization and Iminium Ion Chemistry
%U https://acs.figshare.com/articles/journal_contribution/Synthesis_of_Sedinine_by_Allene_Cyclization_and_Iminium_Ion_Chemistry/2735929
%R 10.1021/ol1016492.s002
%2 https://ndownloader.figshare.com/files/4412668
%K Allene Cyclization
%K semicyclic
%K bicyclic
%K cyclization
%K iminium ions
%K metathesi
%K hydroxylamine
%K allenic
%K silyl enol ether
%K consideration
%K conformation
%K Sedinine
%K acetal
%K synthesis
%K opening
%K conversion
%K Lewis acidic conditions
%K stereoselectivity
%K Iminium Ion Chemistry
%K tran
%K sedum alkaloid sedinine
%K Synthesi
%X A synthesis of the sedum alkaloid sedinine has been achieved employing silver(I)-catalyzed allenic hydroxylamine cyclization and ring-closing metathesis to form a bicyclic N,O-acetal. Ring opening of this acetal with a silyl enol ether under Lewis acidic conditions is exclusively trans selective, leading to the natural product after reduction. On the other hand, conversion of the bicyclic N,O-acetal to a semicyclic N,O-acetal results in no stereoselectivity during such a reaction. The contrasting results can be rationalized by consideration of the conformation of the iminium ions.
%I ACS Publications