Chiral induction by helical neighbour: spectroscopic visualization of macroscopic-interaction among self-sorted donor and acceptor π-stacks

Abstract

Supramolecular induction of chirality to a π-stacked dialkoxynaphthalene (DAN)-fiber (made of achiral building blocks) from a neighbouring helical naphthalenediimide (NDI)-fiber is reported. CD-studies helped in understanding the nature of co-assembly in the donor-acceptor chromophore mixture from molecular to macroscopic scale.

Biocatalytic Self‐Assembly of Supramolecular Charge‐Transfer Nanostructures Based on n‐Type Semiconductor‐Appended Peptides

“…FTIR spectra did not show any peaks in the amide I region (1610 to 1640 cm −1 ), suggesting the absence of a β‐sheet‐like hydrogen‐bonding network (Figure 3 c and Figure S9). Similarly, no peaks were observed in both band I and band II regions of the CD spectra, which suggests that NDI and DAN chromophores were not present in a supramolecular chiral environment (Figure S3) 30. All these observations consistently indicate that the charge‐transfer NDI‐Y acceptor and 1 , 5‐DAN donor pair clearly lacks the ability to form the elongated supramolecular charge‐transfer nanofibers.…”

The sensitivity of donor – acceptor charge transfer to molecular geometry in DAN – NDI based supramolecular flower-like self-assemblies

“…The polarization of the aromatic systems lays the basis for the energetic interaction between the two π systems. Face centred interactions between NDI and DAN can occur because of the complementary geometry of the quadruple polarization in the NDI, and the reversal quadruple polarization in the DAN aromatic system 11 , 13 . These alternating electron-deficient and electron-rich aromatic molecules can stack in an arrangement that results in the through space mixing of adjacent π orbitals, providing the basis for charge transfer between the two molecules.…”

Сhiral and Racemic Fields Concept for Understanding of the Homochirality Origin, Asymmetric Catalysis, Chiral Superstructure Formation from Achiral Molecules, and B-Z DNA Conformational Transition

“…Reaction mixture structuring by means of physical gel and π-π* stacking or H-bonding relationships of interacting molecules is necessary for displaying chiral memory in the formation of chiral superstructures. These relations and the chiral memory effect were observed for self-assembly of molecules 56 [231] and 57 [216], and other aromatic molecules in the presence of molecular low weight gelators [217,[229][230][231]. The idea of reaction mixture media structuring with gel has been further evolved experimentally [232][233][234][235].…”

“…It is believed that the gel formation leads to reaction medium structuring. Together with ππ * stacking [227,228], H-bonding [229], and donor-acceptor interaction [230], this structuring facilitates the chiral information transfer. Polymers 54 and 55 form co-gels with the N,N'-bis(octadecyl)L(D)-Boc-glutamic gelator [218].…”