Oxazoline-Thiourea as a Bifunctional Organocatalyst: Enantioselective aza-Henry Reactions

Abstract

Bifunctional oxazoline-thiourea-based organocatalysts were synthesized and applied to the aza-Henry reactions between N-Boc aryl imines and nitromethane in high ee and chemical yields at room temperature.

Key words

oxazoline - thiourea - aza-Henry reactions - organocatalyst

References and Notes

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14

Representative Procedure To a stirred solution of N-Boc phenyl imines (1 mmol) and the catalyst (0.1 mmol) in THF (2 mL) was added MeNO₂ (10 mmol), and the mixture was stirred for 24 h at r.t. Then the reaction mixture was condensed under reduced pressure, and the obtained residue was purified by column chromatog-raphy on silica gel to afford desired product 6a (93% yield).