Asymmetric lithiation trapping of N -boc heterocycles at temperatures above -78°C

Giacomo Gelardi, Graeme Barker, Peter O'Brien*, David C. Blakemore

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


The asymmetric lithiation trapping of N-Boc heterocycles using s-BuLi/chiral diamines at temperatures up to -20°C is reported. Depending on the N-Boc heterocycle, lithiation is accomplished using s-BuLi and (-)-sparteine or the (+)-sparteine surrogate in the temperature range -50 to -20°C for short reaction times (2-20 min). Subsequent electrophilic trapping or transmetalation-Negishi coupling delivered functionalized N-Boc heterocycles in 47-95% yield and 77:23-93:7 er. With N-Boc pyrrolidine, trapped products can be generated in ∼90:10 er even at -20°C.

Original languageEnglish
Pages (from-to)5424-5427
Number of pages4
JournalOrganic Letters
Issue number21
Early online date15 Oct 2013
Publication statusPublished - 1 Nov 2013

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