title: Counteranion Driven Homochiral Assembly of a Cationic C3-Symmetric Gelator through Ion-Pair Assisted Hydrogen Bond.
abstract: The helical handedness in achiral self-assemblies is mostly complex due to spontaneous symmetry breaking or kinetically controlled random assembly formation. Here an attempt has been made to address this issue through chiral anion exchange. A new class of cationic achiral C3-symmetric gelator devoid of any conventional gelation assisting functional units is found to form both right- and left-handed helical structures. A chiral counteranion exchange-assisted approach is successfully introduced to control the chirality sign and thereby to obtain preferred homochiral assemblies. Formation of anion-assisted chiral assembly was confirmed by circular dichroism (CD) spectroscopy, microscopic images, and crystal structure. The X-ray crystal structure reveals the construction of helical assemblies with opposite handedness for (+)- and (-)-chiral anion reformed gelators. The appropriate counteranion driven ion-pair-assisted hydrogen-bonding interactions are found responsible for the helical bias control in this C3-symmetric gelator.
authors: Arunava
authors: A
authors: Maity
authors: Monalisa
authors: M
authors: Gangopadhyay
authors: Arghya
authors: A
authors: Basu
authors: Sunil
authors: S
authors: Aute
authors: Sukumaran Santhosh
authors: SS
authors: Babu
authors: CSIR-Central Salt & Marine Chemicals Research Institute , Bhavnagar 364002, Gujarat, India.
authors: Amitava
authors: A
authors: Das