Reactivity series for s-BuLi/diamine-mediated lithiation of N-Boc pyrrolidine: applications in catalysis and lithiation of N-Boc piperidine.
نویسندگان
چکیده
Using competition experiments between a range of ligands and (-)-sparteine, a reactivity series for N-Boc pyrrolidine lithiation using s-BuLi/diamines has been constructed; the results indicate that the s-BuLi/(+)-sparteine surrogate complex is more reactive than s-BuLi/(-)-sparteine and this has been exploited in the selection of ligand pairs for ligand exchange catalytic asymmetric lithiation of N-Boc pyrrolidine and lithiation of N-Boc piperidine.
منابع مشابه
Mechanistic interrogation of the asymmetric lithiation-trapping of N-thiopivaloyl azetidine and pyrrolidine.
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عنوان ژورنال:
- Chemical communications
دوره 24 شماره
صفحات -
تاریخ انتشار 2006