Optical Activity and Optical Anisotropy in Photomechanical Crystals of Chiral Salicylidenephenylethylamines

Akifumi Takanabe, Masahito Tanaka, Kohei Johmoto, Hidehiro Uekusa, Tadashi Mori, Hideko Koshima, Toru Asahi

    Research output: Contribution to journalArticle

    15 Citations (Scopus)

    Abstract

    Introducing chirality into photomechanical crystals is beneficial for the diversification of mechanical motion. Measurement of the chiroptical and optical anisotropic properties of chiral crystals is indispensable for evaluating photomechanical crystals. The platelike crystals of S- and R-enantiomers of photochromic N-3,5-di-tert-butylsalicylidene-1-phenylethylamine in enol form (enol-(S)-1 and enol-(R)-1) caused bending motion with twisting upon ultraviolet (UV) light irradiation, due to shrinkage along the length and width directions of the irradiated surface, based on the optimized crystal structure of the photoisomerized trans-keto-(S)-1. By employing the generalized high-accuracy universal polarimeter (G-HAUP), optical anisotropic (linear birefringence, LB; linear dichroism, LD) as well as chiroptical (circular birefringence, CB; circular dichroism, CD) spectra of both the enantiomeric crystals on the (001) face were simultaneously measured before and under continuous UV irradiation. The LD peak was observed at 330 nm in the negative sign, derived from the π-π∗ transition of the intramolecularly hydrogen-bonded salicylidenimino moiety. The CD spectra of the S and R crystals revealed the negative and positive Cotton effect at 330 nm, respectively, and new peaks appeared at 460 nm under UV light irradiation due to photoisomerization to the S and R trans-keto isomers at around 10% conversion. The CB and CD spectra evaluated by the HAUP measurement were opposite to those measured in the hexane solution, as well as those simulated by quantum chemical calculation. The dissymmetry parameter, g, of the enol-(S)-1 crystal along the c axis (0.013) was approximately 10 times larger than the g values in the solution (0.0010) and by calculation (0.0016).

    Original languageEnglish
    Pages (from-to)15066-15077
    Number of pages12
    JournalJournal of the American Chemical Society
    Volume138
    Issue number45
    DOIs
    Publication statusPublished - 2016 Nov 16

    Fingerprint

    Birefringence
    Optical Rotation
    Optical anisotropy
    Anisotropy
    Ultraviolet Rays
    Phenethylamines
    Crystals
    Hexanes
    Circular Dichroism
    Hydrogen
    Dichroism
    Irradiation
    Photoisomerization
    Polarimeters
    Enantiomers
    Chirality
    Hexane
    Isomers
    Cotton
    Crystal structure

    ASJC Scopus subject areas

    • Catalysis
    • Chemistry(all)
    • Biochemistry
    • Colloid and Surface Chemistry

    Cite this

    Optical Activity and Optical Anisotropy in Photomechanical Crystals of Chiral Salicylidenephenylethylamines. / Takanabe, Akifumi; Tanaka, Masahito; Johmoto, Kohei; Uekusa, Hidehiro; Mori, Tadashi; Koshima, Hideko; Asahi, Toru.

    In: Journal of the American Chemical Society, Vol. 138, No. 45, 16.11.2016, p. 15066-15077.

    Research output: Contribution to journalArticle

    Takanabe, Akifumi ; Tanaka, Masahito ; Johmoto, Kohei ; Uekusa, Hidehiro ; Mori, Tadashi ; Koshima, Hideko ; Asahi, Toru. / Optical Activity and Optical Anisotropy in Photomechanical Crystals of Chiral Salicylidenephenylethylamines. In: Journal of the American Chemical Society. 2016 ; Vol. 138, No. 45. pp. 15066-15077.
    @article{f7f1de730d844a709c502d29198eded0,
    title = "Optical Activity and Optical Anisotropy in Photomechanical Crystals of Chiral Salicylidenephenylethylamines",
    abstract = "Introducing chirality into photomechanical crystals is beneficial for the diversification of mechanical motion. Measurement of the chiroptical and optical anisotropic properties of chiral crystals is indispensable for evaluating photomechanical crystals. The platelike crystals of S- and R-enantiomers of photochromic N-3,5-di-tert-butylsalicylidene-1-phenylethylamine in enol form (enol-(S)-1 and enol-(R)-1) caused bending motion with twisting upon ultraviolet (UV) light irradiation, due to shrinkage along the length and width directions of the irradiated surface, based on the optimized crystal structure of the photoisomerized trans-keto-(S)-1. By employing the generalized high-accuracy universal polarimeter (G-HAUP), optical anisotropic (linear birefringence, LB; linear dichroism, LD) as well as chiroptical (circular birefringence, CB; circular dichroism, CD) spectra of both the enantiomeric crystals on the (001) face were simultaneously measured before and under continuous UV irradiation. The LD peak was observed at 330 nm in the negative sign, derived from the π-π∗ transition of the intramolecularly hydrogen-bonded salicylidenimino moiety. The CD spectra of the S and R crystals revealed the negative and positive Cotton effect at 330 nm, respectively, and new peaks appeared at 460 nm under UV light irradiation due to photoisomerization to the S and R trans-keto isomers at around 10{\%} conversion. The CB and CD spectra evaluated by the HAUP measurement were opposite to those measured in the hexane solution, as well as those simulated by quantum chemical calculation. The dissymmetry parameter, g, of the enol-(S)-1 crystal along the c axis (0.013) was approximately 10 times larger than the g values in the solution (0.0010) and by calculation (0.0016).",
    author = "Akifumi Takanabe and Masahito Tanaka and Kohei Johmoto and Hidehiro Uekusa and Tadashi Mori and Hideko Koshima and Toru Asahi",
    year = "2016",
    month = "11",
    day = "16",
    doi = "10.1021/jacs.6b09633",
    language = "English",
    volume = "138",
    pages = "15066--15077",
    journal = "Journal of the American Chemical Society",
    issn = "0002-7863",
    publisher = "American Chemical Society",
    number = "45",

    }

    TY - JOUR

    T1 - Optical Activity and Optical Anisotropy in Photomechanical Crystals of Chiral Salicylidenephenylethylamines

    AU - Takanabe, Akifumi

    AU - Tanaka, Masahito

    AU - Johmoto, Kohei

    AU - Uekusa, Hidehiro

    AU - Mori, Tadashi

    AU - Koshima, Hideko

    AU - Asahi, Toru

    PY - 2016/11/16

    Y1 - 2016/11/16

    N2 - Introducing chirality into photomechanical crystals is beneficial for the diversification of mechanical motion. Measurement of the chiroptical and optical anisotropic properties of chiral crystals is indispensable for evaluating photomechanical crystals. The platelike crystals of S- and R-enantiomers of photochromic N-3,5-di-tert-butylsalicylidene-1-phenylethylamine in enol form (enol-(S)-1 and enol-(R)-1) caused bending motion with twisting upon ultraviolet (UV) light irradiation, due to shrinkage along the length and width directions of the irradiated surface, based on the optimized crystal structure of the photoisomerized trans-keto-(S)-1. By employing the generalized high-accuracy universal polarimeter (G-HAUP), optical anisotropic (linear birefringence, LB; linear dichroism, LD) as well as chiroptical (circular birefringence, CB; circular dichroism, CD) spectra of both the enantiomeric crystals on the (001) face were simultaneously measured before and under continuous UV irradiation. The LD peak was observed at 330 nm in the negative sign, derived from the π-π∗ transition of the intramolecularly hydrogen-bonded salicylidenimino moiety. The CD spectra of the S and R crystals revealed the negative and positive Cotton effect at 330 nm, respectively, and new peaks appeared at 460 nm under UV light irradiation due to photoisomerization to the S and R trans-keto isomers at around 10% conversion. The CB and CD spectra evaluated by the HAUP measurement were opposite to those measured in the hexane solution, as well as those simulated by quantum chemical calculation. The dissymmetry parameter, g, of the enol-(S)-1 crystal along the c axis (0.013) was approximately 10 times larger than the g values in the solution (0.0010) and by calculation (0.0016).

    AB - Introducing chirality into photomechanical crystals is beneficial for the diversification of mechanical motion. Measurement of the chiroptical and optical anisotropic properties of chiral crystals is indispensable for evaluating photomechanical crystals. The platelike crystals of S- and R-enantiomers of photochromic N-3,5-di-tert-butylsalicylidene-1-phenylethylamine in enol form (enol-(S)-1 and enol-(R)-1) caused bending motion with twisting upon ultraviolet (UV) light irradiation, due to shrinkage along the length and width directions of the irradiated surface, based on the optimized crystal structure of the photoisomerized trans-keto-(S)-1. By employing the generalized high-accuracy universal polarimeter (G-HAUP), optical anisotropic (linear birefringence, LB; linear dichroism, LD) as well as chiroptical (circular birefringence, CB; circular dichroism, CD) spectra of both the enantiomeric crystals on the (001) face were simultaneously measured before and under continuous UV irradiation. The LD peak was observed at 330 nm in the negative sign, derived from the π-π∗ transition of the intramolecularly hydrogen-bonded salicylidenimino moiety. The CD spectra of the S and R crystals revealed the negative and positive Cotton effect at 330 nm, respectively, and new peaks appeared at 460 nm under UV light irradiation due to photoisomerization to the S and R trans-keto isomers at around 10% conversion. The CB and CD spectra evaluated by the HAUP measurement were opposite to those measured in the hexane solution, as well as those simulated by quantum chemical calculation. The dissymmetry parameter, g, of the enol-(S)-1 crystal along the c axis (0.013) was approximately 10 times larger than the g values in the solution (0.0010) and by calculation (0.0016).

    UR - http://www.scopus.com/inward/record.url?scp=84996540032&partnerID=8YFLogxK

    UR - http://www.scopus.com/inward/citedby.url?scp=84996540032&partnerID=8YFLogxK

    U2 - 10.1021/jacs.6b09633

    DO - 10.1021/jacs.6b09633

    M3 - Article

    AN - SCOPUS:84996540032

    VL - 138

    SP - 15066

    EP - 15077

    JO - Journal of the American Chemical Society

    JF - Journal of the American Chemical Society

    SN - 0002-7863

    IS - 45

    ER -