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Rotational Isomerism of an Amide Substituted Squaraine Dye: A Combined Spectroscopic and Computational Study.

ABSTRACT: The conformational analysis of a 2,4-bis(4-dialkylamino-2-amido)phenyl squaraine dye revealed the presence of two rotational isomers at room temperature. Combination of spectroscopic and computational techniques showed that the rotational barrier is influenced by hydrogen bonds between the amido substituents and the oxygen atoms at the quadratic core. Even small amounts of trifluoroacetic acid interfered with the intramolecular hydrogen bond formation and accelerated the interconversion of the conformers.

SUBMITTER: Rosch AT

PROVIDER: S-EPMC8453623 | biostudies-literature | 2021 Sep

REPOSITORIES: biostudies-literature

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Rotational Isomerism of an Amide Substituted Squaraine Dye: A Combined Spectroscopic and Computational Study.

Rösch Andreas T AT Söntjens Serge H M SHM Robben Jorn J Palmans Anja R A ARA Schnitzer Tobias T

The Journal of organic chemistry 20210901 18

The conformational analysis of a 2,4-bis(4-dialkylamino-2-amido)phenyl squaraine dye revealed the presence of two rotational isomers at room temperature. Combination of spectroscopic and computational techniques showed that the rotational barrier is influenced by hydrogen bonds between the amido substituents and the oxygen atoms at the quadratic core. Even small amounts of trifluoroacetic acid interfered with the intramolecular hydrogen bond formation and accelerated the interconversion of the c ...[more]

PMID: 34469161

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Dataset Information

Rotational Isomerism of an Amide Substituted Squaraine Dye: A Combined Spectroscopic and Computational Study.

Publications

Rotational Isomerism of an Amide Substituted Squaraine Dye: A Combined Spectroscopic and Computational Study.

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