Chemoenzymatic Synthesis of an Odanacatib Precursor through a Suzuki‐Miyaura Cross‐Coupling and Bioreduction Sequence

A series of 1‐aryl‐2,2,2‐trifluoroethanones has been chemically synthesized to later study their bioreduction using stereocomplementary alcohol dehydrogenases (ADHs). Satisfyingly, (R)‐alcohols were obtained in high conversions and selectivities using the ADH from Ralstonia species and the one from Rhodococcus ruber, while the (S)‐enantiomers were independently produced using the ADH from Lactobacillus brevis and the commercially available evo‐1.1.200. In the search for a stereoselective route towards the Odanacatib, an orally bioavailable and selective inhibitor of Cathepsin K, the development of a sequential methodology combining a palladium‐catalyzed cross coupling between 1‐(4‐bromophenyl)‐2,2,2‐trifluoroethanone and 4‐(methylsulfonyl)phenylboronic acid in aqueous medium with the bioreduction of the resulting 2,2,2‐trifluoro‐1‐(4′‐(methylsulfonyl)‐[1,1′‐biphenyl]‐4‐yl)ethanone has been extensively studied. Finally, the desired (R)‐2,2,2‐trifluoro‐1‐(4′‐(methylsulfonyl)‐[1,1′‐biphenyl]‐4‐yl)ethanol was obtained in enantiomerically pure form and 85 % yield with a 128 g L−1 d−1 productivity following a sequential approach. The perfect partnership: A good compatibility between palladium and alcohol dehydrogenase from Ralstonia species has been found for the successful development of a sequential chemoenzymatic transformation towards the formation of a valuable enantiopure Odanacatib precursor.