Stereodivergent Preparation of Valuable gamma- or delta-Hydroxy Esters and Lactones through One-Pot Cascade or Tandem Chemoenzymatic Protocols

作者：Diaz Rodriguez Alba; Borzecka Wioleta; Lavandera Ivan^*; Gotor Vicente

来源：ACS Catalysis, 2014, 4(2): 386-393.

DOI：10.1021/cs4010024

• alcohol dehydrogenases
• lactones
• cascade reaction
• tandem reaction
• palladium-catalyzed cross-coupling

A series of enantiopure hydroxy esters and lactones has been synthesized in a chemodivergent manner via alcohol dehydrogenase (ADH) reduction of the corresponding keto esters by means of cascade or tandem protocols. Thus, ADH from Rhodococcus ruber (ADH-A) or Lactobacillus brevis (LBADH) afforded both antipodes in a very selective way when dealing with small derivatives. With bulkier substrates, ADH from Ralstonia sp. (RasADH) was successfully employed to achieve the synthesis of enantioenriched gamma- or delta-hydroxy esters. To isolate the corresponding lactones, two different approaches were followed: a cascade reaction by spontaneous cyclization of the hydroxy ester intermediate, or a one-pot two-step tandem protocol. Moreover, a chemoenzymatic route was designed to obtain a chiral brominated lactone, which enabled further modifications in a sequential fashion by Pd-catalyzed reactions, affording relevant functionalized lactones.

• 出版日期2014-2