Dynamics of Hydrogen Bonding in Three-Component Nanorotors.

ABSTRACT: The dynamics of hydrogen bonding do not only play an important role in many biochemical processes but also in Nature's multicomponent machines. Here, a three-component nanorotor is presented where both the self-assembly and rotational dynamics are guided by hydrogen bonding. In the rate-limiting step of the rotational exchange, two phenolic O-H-N,N(phenanthroline) hydrogen bonds are cleaved, a process that was followed by variable-temperature 1 H?NMR spectroscopy. Activation data (?G? 298 =46.7?kJ?mol-1 at 298?K, ?H? =55.3?kJ?mol-1 , and ?S? =28.8?J?mol-1 ?K-1 ) were determined, furnishing a rotational exchange frequency of k298 =40.0?kHz. Fully reversible disassembly/assembly of the nanorotor was achieved by addition of 5.0?equivalents of trifluoroacetic acid (TFA)/1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) over three cycles.

SUBMITTER: Biswas PK 

PROVIDER: S-EPMC7702118 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature