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n a study that could help change the way chiral amino acids are synthesized in the pharmaceutical and fine chemicals industries, two groups have developed proline-catalyzed reactions for derivatizing aldehydes and ketones. The reactions use the amino acid proline as a benign organocatalyst. And the ketone a-amination gives equally easy access to optically active -hydrazino and -amino ketones, as well as a range of -amino alcohols.
Both reactions are efficient and highly selective, with yields and enantioselectivities often around 90% and sometimes exceeding 95%. "Major fine chemicals companies should be interested in the reactions because of their potential to make enantiomerically pure amino acids in a one-pot process," Such catalytic asymmetric -amination reactions have generally required the use of preformed enolates of aldehydes and ketones as substrates. The ability to use unmodified aldehydes and ketones instead of preformed enolates simplifies the process considerably.
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