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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

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Dynamics of Hydrogen Bonding in Three-Component Nanorotors.

Biswas Pronay Kumar PK Goswami Abir A Saha Suchismita S Schmittel Michael M

Chemistry (Weinheim an der Bergstrasse, Germany) 20201006 62

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<sub>(phenanthroline)</sub> hydrogen bonds are cleaved, a process that was followed by variable-temperature <sup>1</sup> H NMR spectroscopy. Activatio ...[more]

PMID: 32744381

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