Electrospinning of Cellulose Benzyl Carbamates for Enantioselective Membrane Filtration

Abstract

Electrospun nanofibrous membranes made of chiral selectors (CSs) have shown their potential for efficient chiral resolutions via filtrations. It is thus of great importance to expand the number of electrospun membranes made of various CSs for the resolution of a wide range of chiral compounds. Here, the electrospinning of two benzyl carbamate derivatives of cellulose, namely cellulose benzyl carbamate (CBzC) and cellulose 4-chlorobenzyl carbamate (CCBzC), to form a new type of enantioselective membranes for chiral resolutions of racemic compounds, is reported. The morphology of the electrospun membranes is studied by optical microscopy and scanning electron microscopy in relation to the electrospinning process parameters. Liquid-liquid permeation experiments of the racemic compounds, (R,S)-1-(1-naphthyl)ethanol ((R,S)-NET), (R,S)-1,1′-bi-2-naphtol ((R,S)-BNP), (R,S)-naproxen ((R,S)-NAP), and (R,S)-benzoin ((R,S)-BNZ) through the membranes demonstrate preferable permeations of (R)- or (S)-enantiomers depending on the combinations between the CSs and the racemates. Molecular docking simulations indicate the differences in the binding type, number, and free energies between the CSs and the enantiomers.