New Enzymatic Two‐Step Cascade Reaction for the Preparation of a Key Intermediate for the Taxol Side‐Chain

Enzymatic strategies are reported for the synthesis of (2R,3S)‐3‐amino‐2‐hydroxy‐3‐phenylpropionic acid (ee > 98 %), a key intermediate of the side‐chain of Taxol®, by enzymatic hydrolysis in organic media. The new enzymatic cascade reaction, which took place through Candida antarctica lipase B‐catalysed deacylation followed by lactam ring‐opening of racemic cis‐3‐acetoxy‐4‐phenylazetidin‐2‐one with H2O in iPr2O at 60 °C, resulted in two different enantiopure products (ee ≥ 98 %), one of them being the desired key intermediate for the side‐chain of Taxol®.