73231-34-2 An efficient enantioselective synthesis of florfenicol based on sharpless asymmetric dihydroxylation

An efficient and highly enantioselective synthesis of florfenicol- via a new intermediate threo-dihydroxy ester, with a Sharpless asymmetric dihydroxylation as the key step, is reported. A ring-opening/reduction strategy avoids the formation of a chlorinated byproduct that occurs in Schumachers phenyloxazoline procedure. The overall yield of florfenicol by this new process is 23% based on 4-(methylsulfonyl)benzaldehyde. Georg Thieme Verlag Stuttgart · New York. https://www.lookchem.com/CASDataBase_73231-34-2.htm

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