Solvent-dependent fluorescence and circular dichroism properties of poly(quinoxaline-2,3-diyl)s bearing pyrene pendants.
نویسندگان
چکیده
Poly(quinoxaline-2,3-diyl)s bearing pyrene pendants exhibited solvent-dependent changes of the fluorescence color (blue and green) and the screw-sense selectivity (left-handed and racemic) in chloroform and 1,1,1-trichloroethane, respectively.
منابع مشابه
Non-hydrogen-bonding-based, solvent-dependent helix inversion between pure P-helix and pure M-helix in poly(quinoxaline-2,3-diyl)s bearing chiral side chains.
Poly(quinoxaline-2,3-diyl)s bearing chiral (R)-2-butoxy side chains adopt pure right- or left-handed screw senses in CHCl(3) and 1,1,2-trichloroethane, respectively.
متن کاملChirality-switchable circularly polarized luminescence in solution based on the solvent-dependent helix inversion of poly(quinoxaline-2,3-diyl)s.
Poly(quinoxaline-2,3-diyl)s containing (S)-2-methylbutoxy side chains were found to exhibit blue circularly polarized luminescence (CPL). The handedness of the CPL could be switched by a solvent-dependent helix inversion of the polymer backbone between chloroform (M-helical structure) and 1,1,1-trichloroethane (P-helical structure).
متن کاملPressure-dependent helix inversion of poly(quinoxaline-2,3-diyl)s containing chiral side chains in non-aqueous solvents.
Poly(quinoxaline-2,3-diyl)s with chiral (S)-2-butoxymethyl side chains dissolved in 1,2-dichloroethane experience a reversible pressure-dependent helix inversion from P- to M-helical structures between 0.1 MPa and 200 MPa.
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Single-handed PQXphos, i.e., helical poly(quinoxaline-2,3-diyl)s bearing diarylphosphino pendant groups, served as remarkable chiral ligands in palladium-catalyzed asymmetric hydrosilylation of styrenes and asymmetric biaryl synthesis by Suzuki–Miyaura coupling, affording up to 98 % enantiomeric excess (e.e.) in both reactions. A palladium complex of high-molecular-weight variant (1000mer) of P...
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Solvent chirality transfer of (S)-/(R)-limonenes allows the instant generation of optically active PF8P2 aggregates with distinct circular dichroism (CD)/circularly polarized luminescence (CPL) amplitudes with a high quantum yield of 16-20%. The present paper also reports subtle mirror-symmetry-breaking effects in CD-/CPL-amplitude and sign, CD/UV-vis spectral wavelengths, and photodynamics of ...
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ورودعنوان ژورنال:
- Chemical communications
دوره 48 91 شماره
صفحات -
تاریخ انتشار 2012