TY - JOUR
T1 - Optically active oxo(phthalocyaninato)vanadium(IV) with geometric asymmetry
T2 - Synthesis and correlation between the circular dichroism sign and conformation
AU - Kobayashi, Nagao
AU - Narita, Fumiko
AU - Ishii, Kazuyuki
AU - Muranaka, Atsuya
PY - 2009/10/5
Y1 - 2009/10/5
N2 - Oxovanadium(IV) phthalocyanines (VOPcs) with a single-handed rotation have been prepared, and their right- and left-handed enantiomers resolved on a chiral HPLC column. These enantiomers gave circular dichroism (CD) spectra of opposite signs; the correlation between the CD sign and conformation was obtained by time-dependent density functional theory (TDDFT) calculations: an enantiomer showing a negative sign in the Q band was suggested to be the righthanded conformer viewing from the axial oxygen side, whereas that giving a positive CD sign was assigned to the left-handed conformer. Although silicon phthalocyanines (SiPcs) with two different alkoxy axial ligands have been resolved similarly, the absence of a meaningful CD difference probably reflects the flat character of the SiPc plane compared to the VOPc plane. Changes in the Q-band CD, depending on the relative orientation of the peripheral substituents, have been worked out theoretically and the origin of the chiroptical properties is discussed.
AB - Oxovanadium(IV) phthalocyanines (VOPcs) with a single-handed rotation have been prepared, and their right- and left-handed enantiomers resolved on a chiral HPLC column. These enantiomers gave circular dichroism (CD) spectra of opposite signs; the correlation between the CD sign and conformation was obtained by time-dependent density functional theory (TDDFT) calculations: an enantiomer showing a negative sign in the Q band was suggested to be the righthanded conformer viewing from the axial oxygen side, whereas that giving a positive CD sign was assigned to the left-handed conformer. Although silicon phthalocyanines (SiPcs) with two different alkoxy axial ligands have been resolved similarly, the absence of a meaningful CD difference probably reflects the flat character of the SiPc plane compared to the VOPc plane. Changes in the Q-band CD, depending on the relative orientation of the peripheral substituents, have been worked out theoretically and the origin of the chiroptical properties is discussed.
KW - Circular dichroism
KW - Configuration determination
KW - Density functional calculations
KW - Phthalocyanines
KW - UV/Vis spectroscopy
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U2 - 10.1002/chem.200901306
DO - 10.1002/chem.200901306
M3 - Article
C2 - 19711387
AN - SCOPUS:70349673113
VL - 15
SP - 10173
EP - 10181
JO - Chemistry - A European Journal
JF - Chemistry - A European Journal
SN - 0947-6539
IS - 39
ER -