Regioselective N-alkylation of 1,3-azoles is a valuable transformation. Organomagnesium reagents were discovered to be competent bases to affect regioselective alkylation of various 1,3-azoles. Counterintuitively, substitution selectively occurred at the more sterically hindered nitrogen atom. Numerous examples are provided, on varying 1,3-azole scaffolds, with yields ranging from 25 to 95%.
Direct, Regioselective <i>N</i>-Alkylation of 1,3-Azoles
作者:Shuai Chen、Russell F. Graceffa、Alessandro A. Boezio
DOI:10.1021/acs.orglett.5b02994
日期:2016.1.4
Regioselective N-alkylation of 1,3-azoles is a valuable transformation. Organomagnesium reagents were discovered to be competent bases to affect regioselective alkylation of various 1,3-azoles. Counterintuitively, substitution selectively occurred at the more sterically hindered nitrogen atom. Numerous examples are provided, on varying 1,3-azole scaffolds, with yields ranging from 25 to 95%.
Process for the production of penems
申请人:Schering Corporation
公开号:US04584133A1
公开(公告)日:1986-04-22
Improved processes for the production of 6-hydroxyethyl-2-substituted thio penem-3-carboxylates which eliminate the step of using a silver reagent are disclosed.