Ein neuartiger chiraler Synthesebaustein mit Neopentangerüst: Chemo‐enzymatische Darstellung von ( R )‐CH 3 C(CH 2 OSO 2 CF 3 )(CH 2 Cl)(CH 2 Br)

A Novel Chiral Building Block with Neopentane Framework for Synthesis: Chemo‐Enzymatic Preparation of ( R )‐CH 3 C(CH 2 OSO 2 CF 3 )(CH 2 Cl)(CH 2 Br) The pig liver esterase (PLE) catalysed hydrolysis of the prochiral malonic ester (BzlOCH 2 )(Me)C(COOMe) 2 ( 1 ) leads to its chiral monoester 2 in selectivities up to 81% ee. Compound 2 is an ideal entry point for the enantioselective synthesis of 1,1′,1″‐substituted neopentanes CH 3 C(CH 2 X)‐(CH 2 Y)(CH 2 Z) with three different leaving groups, X, Y, and Z. CH 3 C(CH 2 OSO 2 CF 3 )(CH 2 Br)(CH 2 Cl) ( 8 ) is a versatile reactive building block for the asymmetric synthesis of compounds containing the neopentane‐C 5 skeleton.