Current time in Korea 14:53 Oct 17 (Tue) Year 2017 KCS KCS Publications
KCS Publications
My Journal Log In Register
HOME > Search > Browsing(BKCS) > Archives

Bulletin of the Korean Chemical Society (BKCS)

ISSN 0253-2964(Print)
ISSN 1229-5949(Online)
Volume 33, Number 9
BKCSDE 33(9)
September 20, 2012 

 
Title

Theoretical Analysis on Molecular Magnetic Properties of N-Confused Porphyrins and Its Derivatives

Author
Wei Wei, Fu-Quan Bai, Bao-Hui Xia, Hong-Xing Zhang*
Keywords
Heteroporphyins, Hetero-N-confused porphyrins, NICS, π current density, 1H NMR
Abstract
We have theoretically investigated the magnetic properties of N-confused porphyrin (NCP), tetraphenyl-Nconfused porphyrin (TPNCP) and their substituted derivatives with O, S and Se heteroatoms (2ONCP, 2STPNCP, 2SeNCP, 2OTPNCP, etc.) by using DFT method. In the minimum energy structures of the 2OTPNCP, the two couples opposite phenyl substitutes are staggered. In the case of TPNCP, 2STPNCP and 2SeTPNCP, two phenyls being respectively close to or opposite to N-confused pyrrole are found to be pointed the same direction, whilst others are in the opposite direction. Based on the equilibrium structures, the 1H chemical shifts and nucleus-independent chemical shifts (NICS) are calculated in this paper. The π current density being induced by the tridimensional perpendicular magnetic field transmits the inner section of the pyrrole segments for NCP and TPNCP. As for their substituted derivatives with O, S and Se atoms, the current path passes through the outer section of the two heterorings. The NICS values at the ring critical points of the heterorings are much lower (in absolute value) than those of which is at the center of an isolated pyrrole molecule. The 1H NMR for β H atoms of the heterorings decreases from O, S to with Se.
Page
2937 - 2942
Full Text
PDF