%0 Journal Article %J Journal of Molecular Structure %D 2021 %T Crystal structure analysis of highly efficient chiral resolution of (RS)-arginine-fumaric acid cocrystal under preferential enrichment conditions %A Manoj, Kochunnoonny %A Takahashi, Hiroki %A Iwama, Sekai %A Gonnade, G. Rajesh %A Tsue, Hirohito %A Tamura, Rui %K Arginine %K cocrystals %K crystal structure %K Enantiomeric resolution %K preferential enrichment %X Two new hydrate cocrystals, (RS)-arginine-fumaric acid-H2O ( 2 ) and (S)-arginine-2 fumaric acid-H2O ( 3 ), were obtained by the slow evaporation of the saturated aqueous ethanol solution of a 1:1 mixture of S-enriched arginine (33% ee) and fumaric acid or (S)-arginine and fumaric acid, respectively. Cocrystals 2 and 3 possess an isostructural molecular organization containing homochiral 1D chains of arginine sim-ilar to that of the anhydrous cocrystal of (RS)-arginine-fumaric acid ( 1 ). The latter showed an efficient ``preferential enrichment (PE)'', a unique spontaneous enantiomeric resolution phenomenon by simple recrystallization from the highly supersaturated solution. The formation of unstable cocrystals 2 and 3 seems to have played a crucial role in the enrichment of arginine in the mother liquor under PE crystal-lization conditions. (c) 2021 Elsevier B.V. All rights reserved. %B Journal of Molecular Structure %V 1245 %P 131073 %8 DEC %G eng %9 Article %3 Foreign %4 3.196 %R 10.1016/j.molstruc.2021.131073