Urea/Transition-Metal Cooperative Catalyst for anti-Selective Asymmetric Nitroaldol Reactions


  • This work was supported by the U.S. National Science Foundation (Grant CHE-0957643).


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A cooperative catalyst that features urea H-bonding and a cobalt center was developed for anti-selective asymmetric Henry reactions (see scheme). The H-bonds of urea play a crucial role in the improvement in yield (from 30 % to 84 %), enantioselectivity (from 78 % to 96 %), and anti diastereoselectivity (from 3:1 to 48:1). A short synthesis of (1R,2S)-methoxamine hydrochloride was also accomplished with this catalyst.