Diamine-free lithiation-trapping of N-Boc heterocycles using s-BuLi in THF.
A diamine-free protocol for the s-BuLi-mediated lithiation-trapping of N-Boc heterocycles has been developed. In the optimized procedure, lithiation is accomplished using s-BuLi in THF at -30 °C for only 5 or 10 min. Subsequent electrophilic trapping or transmetalation-Negishi coupling delivered a range of functionalized pyrrolidines, imidazolidines, and piperazines in 43-83% yield.
Barker
Graeme
G
Department of Chemistry, University of York, Heslington, York YO10 5DD, UK.
O'Brien
Peter
P
Campos
Kevin R
KR
D003959:Diamines / Q000737:chemistry; D005663:Furans / Q000737:chemistry; D006571:Heterocyclic Compounds / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D013237:Stereoisomerism
D003959:Diamines; D005663:Furans; D006571:Heterocyclic Compounds; D009942:Organometallic Compounds; C046771:butyllithium; C018674:tetrahydrofuran; D008094:Lithium