Figure-eight thermal hysteresis of aminomethylenehelicene oligomers with terminal C16 alkyl groups during hetero-double-helix formation.
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ABSTRACT:
SUBMITTER: Sawato T
PROVIDER: S-EPMC8157274 | biostudies-literature | 2020 Feb
REPOSITORIES: biostudies-literature
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Figure-eight thermal hysteresis of aminomethylenehelicene oligomers with terminal C<sub>16</sub> alkyl groups during hetero-double-helix formation.
Sawato Tsukasa T Iwamoto Rina R Yamaguchi Masahiko M
Chemical science 20200226 12
1 : 1 mixtures of aminomethylenehelicene (<i>P</i>)-tetramer and (<i>M</i>)-pentamer with terminal C<sub>16</sub> alkyl groups in fluorobenzene showed structural changes between hetero-double-helices <b>B</b> and <b>C</b> and random-coils 2<b>A</b>. Figure-eight thermal hysteresis appeared when the solution was cooled and heated at a constant rate and involved the crossing of cooling and heating curves in Δ<i>ε</i>/temperature profiles. This unusual thermal hysteresis emerged in the intermediate ...[more]
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