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Efficient Cinchona‐derived chiral 2‐aminobenzimidazole catalysts were prepared by the coupling of 5,7‐bis(trifluoromethyl)‐2‐chlorobenzimidazole with C(9S)‐aminodihydroquinine or C(9R)‐aminodihydroquinidine and successively applied to the Michael addition of dimethyl malonate to nitroolefins as very efficient chiral Lewis acid bifunctional organocatalysts (up to >99% ee).
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Zhang et al. (2009) studied this question.
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