Optical Resolution and Spontaneous Resolution in the Self-assembly of Haloperfluoroalkanes
Abstr. Pap. Am. Chem. Soc. 230, 2005, FLUO-024
P. Metrangolo, F. Meyer, G. Resnati
Homochiral halogen-bonded infinite helices
Homochiral halogen-bonded infinite helices
ABSTRACT
Very few resolution processes involving perfluorocarbon compounds have been reported in the literature. In this communication we will describe the resolution and spontaneous resolution processes occuring when the halogen bonding drives the self-assembly of bromo- or iodoperfluoroalkanes with neutral or ionic hydrocarbon derivatives. It will be reported that chiral and racemic haloperfluoroalkanes have been resolved through co-crystal formation with a chiral and enantiopure organic salt. More interestingly, we will also describe various homochiral co-crystals obtained through the self-assembly of non chiral iodoperfluoroalkanes with non chiral hydrocarbon derivatives. In some cases the co-crystal homochirality has a molecular origin as a centrosymmetric molecule adopts exclusively homochiral conformations. In other cases the co-crystals homochirality has a supramolecular origin as enantiopure helixes are formed on self-assembly of non chiral or racemic modules.