Variably isotactic poly(hydroxybutyrate) from racemic β-butyrolactone: Microstructure control by achiral chromium(III) salophen complexes

Abstract

ROP artists: The ROP of racemic β-butyrolactone (BL) catalyzed by highly active chromium(III) salophen complexes 1 gives poly(hydroxybutyrate) (PHB) with high molecular weight and with isotacticities of 60-70%. The product is a biodegradable polymer material with mechanical properties that can be varied from crystalline to thermoplastic. DFT calculations indicate that the induction of stereochemical information occurs through the formation of dimeric cage-like structures. (Chemical Equation Presented). © 2008 Wiley-VCH Verlag GmbH & Co. KGaA.