A series of trifunctional BINAP-based monophosphonium phase-transfer catalysts were developed and used in the asymmetric addition of α-diazomethylphosphonates to vinylogous imines formed in situ from sulfonylindoles. This methodology tolerates a… Click to show full abstract
A series of trifunctional BINAP-based monophosphonium phase-transfer catalysts were developed and used in the asymmetric addition of α-diazomethylphosphonates to vinylogous imines formed in situ from sulfonylindoles. This methodology tolerates a broad scope of 2-unsubstituted sulfonyl indoles, which have seldom achieved high enantioselectivities in similar asymmetric reactions with other nucleophiles. Chiral 3-sec-alkyl-substituted indoles containing α-diazophosphonate were afforded in up to 99% yield and 95% ee.
               
Click one of the above tabs to view related content.