Synthesis of 1-Substituted Tetrahydroisoquinolines by Lithiation and Electrophilic Quenching Guided by In Situ IR and NMR Spectroscopy and Application to the Synthesis of Salsolidine, Carnegine and Laudanosine
作者:Xiabing Li、Daniele Leonori、Nadeem S. Sheikh、Iain Coldham
DOI:10.1002/chem.201301096
日期:2013.6.10
The lithiation of N‐tert‐butoxycarbonyl (N‐Boc)‐1,2,3,4‐tetrahydroisoquinoline was optimized by in situIR (ReactIR) spectroscopy. Optimum conditions were found by using n‐butyllithium in THF at −50 °C for less than 5 min. The intermediate organolithium was quenched with electrophiles to give 1‐substituted 1,2,3,4‐tetrahydroisoquinolines. Monitoring the lithiation by IR or NMRspectroscopy showed that