title: Stimuli-responsive self-assembly of a naphthalene diimide by orthogonal hydrogen bonding and its coassembly with a pyrene derivative by a pseudo-intramolecular charge-transfer interaction.
abstract: A naphthalene diimide (NDI) building block containing hydrazide (H1) and hydroxy (H2) groups self-assembled into a reverse-vesicular structure in methylcyclohexane by orthogonal H-bonding and π-stacking. At an elevated temperature (LCST=43 °C), destruction of the assembled structure owing to selective dissociation of H2-H2 H bonding led to macroscopic precipitation. Further heating resulted in homogeneous redispersion of the sample at 70 °C (UCST) and the formation of a reverse-micellar structure. In the presence of a pyridine (H3)-functionalized pyrene (PY) donor, a supramolecular dyad (NDI-PY) was formed by H2-H3 H-bonding. Slow transformation into an alternate NDI-PY stack occurred by a folding process due to the charge-transfer interaction between NDI and PY. The mixed NDI-PY assembly exhibited a morphology transition from a reverse micelle (with a NDI-PY mixed-stack core) below the LCST to another reverse micelle (with a NDI core) above the UCST via a "denatured" intermediate.
authors.affiliation: Polymer Science Unit, Indian Association for the Cultivation of Science, 2A and 2B Raja S. C. Mullick Road, Kolkata, 700032 (India).
authors.forename: Anindita
authors.initials: A
authors.lastname: Das
authors.forename: Suhrit
authors.initials: S
authors.lastname: Ghosh
mesh_terms: D006860:Hydrogen Bonding; D007094:Imides / Q000138:chemical synthesis* / Q000737:chemistry; D008958:Models, Molecular; D015394:Molecular Structure; D009281:Naphthalenes / Q000138:chemical synthesis* / Q000737:chemistry; D010316:Particle Size; D044367:Phase Transition; D011721:Pyrenes / Q000737:chemistry*; D013499:Surface Properties; D013696:Temperature
chemical_list: D007094:Imides; D009281:Naphthalenes; D011721:Pyrenes; C542131:naphthalenediimide; C030984:pyrene
keywords: charge-transfer interactions; orthogonal hydrogen bonding; reverse micelles; reverse vesicles; thermal transitions