Phenyl-(2-pyridyl)-(3-pyridyl)-(4-pyridyl)methane: synthesis, chiroptical properties, and theoretical calculation of its absolute configuration.
The title compound, a prototypical chiral molecule based on a tetraarylmethane framework, has been synthesized in five steps from (2-pyridyl)-(3-pyridyl)ketone. X-ray crystallographic analysis revealed the tetraarylmethane framework of the molecule but did not determine the positions of the nitrogen atoms because the crystal is a racemic compound and the aryl groups are disordered in the crystal. The optical resolution of the title compound was achieved by chiral HPLC with a Chiralcel OD column. The CD spectra of the two fractions in acetonitrile exhibited opposite signs as expected for a pair of enantiomers. Their CD spectra are changed in 2 M HCl due to protonation. The calculated CD curve for the target molecule based on time-dependent density functional theory (TDDFT) reproduces the experimental result very well, thus suggesting that the first eluted fraction is the R isomer in terms of absolute configuration.
Matsumoto
Kouzou
K
Graduate School of Science, Osaka University, 1-1 Machikaneyamacho, Toyonaka, Osaka 560-0043, Japan. kmatsu@chem.sci.osaka-u.ac.jp
Inagaki
Takuya
T
Nehira
Tatsuo
T
Kannami
Masaki
M
Inokuchi
Daisuke
D
Kurata
Hiroyuki
H
Kawase
Takeshi
T
Pescitelli
Gennaro
G
Oda
Masaji
M
D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D018360:Crystallography, X-Ray; D008958:Models, Molecular; D011725:Pyridines / Q000737:chemistry*; D013237:Stereoisomerism
D011725:Pyridines