ABSTRACT
Both enantiomers of trans-cyclohexane-1,2-diammonium sulfate and trans-1,2-diphenylethylenediammonium sulfate were used as "tailor-made" additives to direct the mirror-symmetry breaking in the attrition-enhanced deracemization (i.e. Viedma ripening) of conglomerate crystals of ethylenediammonium sulfate (EDS). Isothermal titration calorimetry (ITC) shows chiral recognition of (1R,2R)- and (1S,2S)-1,2-diphenylethylenediamine to EDS crystals where the enthalpy of adsorption of the (1R,2R)-isomer on l-EDS crystals is higher in comparison to that on d-EDS crystals. These results are consistent with a "rule of reversal" mechanism driving the chiral outcome of the Viedma ripening of EDS.
ABSTRACT
Directed chiral symmetry breaking and asymmetric amplification of ethylenediammonium sulfate in the presence of chiral amino acids was achieved using an abrasion/grinding method.
Subject(s)
Amino Acids/chemistry , Quaternary Ammonium Compounds/chemistry , Crystallization , Models, Molecular , StereoisomerismABSTRACT
Complete asymmetric amplification of ethylenediammonium sulfate was achieved under continuous dissolution/crystallization conditions using an abrasion/grinding method.
