Molecular modeling and experimental studies on structure and NMR parameters of 9-benzyl-3,6-diiodo-9H-carbazole

TY - JOUR

T1 - Molecular modeling and experimental studies on structure and NMR parameters of 9-benzyl-3,6-diiodo-9H-carbazole

AU - Radula-Janik, Klaudia

AU - Kupka, Teobald

AU - Ejsmont, Krzysztof

AU - Daszkiewicz, Zdzisław

AU - Sauer, Stephan P. A.

PY - 2015/8/25

Y1 - 2015/8/25

N2 - Abstract A combined experimental and theoretical study has been performed on 9-benzyl-3,6-diiodo-9H-carbazole. Experimental X-ray (100.0 K) and room-temperature 13C nuclear magnetic resonance (NMR) studies were supported by advanced density functional theory calculations. The non-relativistic structure optimization was performed and the 13C nuclear magnetic shieldings were predicted at the relativistic level of theory using the zeroth-order regular approximation. The changes in the benzene and pyrrole rings compared to the unsubstituted carbazole or the parent molecules were discussed in terms of aromaticity changes using the harmonic oscillator model of aromaticity and the nucleus independent chemical shift indexes. Theoretical relativistic calculations of chemical shifts of carbons C3 and C6, directly bonded to iodine atoms, produced a reasonable agreement with experiment (initial deviation from experiment of 41.57 dropped to 5.6 ppm). A good linear correlation between experimental and theoretically predicted structural and NMR parameters was observed. Graphical Abstract: [Figure not available: see fulltext.]

AB - Abstract A combined experimental and theoretical study has been performed on 9-benzyl-3,6-diiodo-9H-carbazole. Experimental X-ray (100.0 K) and room-temperature 13C nuclear magnetic resonance (NMR) studies were supported by advanced density functional theory calculations. The non-relativistic structure optimization was performed and the 13C nuclear magnetic shieldings were predicted at the relativistic level of theory using the zeroth-order regular approximation. The changes in the benzene and pyrrole rings compared to the unsubstituted carbazole or the parent molecules were discussed in terms of aromaticity changes using the harmonic oscillator model of aromaticity and the nucleus independent chemical shift indexes. Theoretical relativistic calculations of chemical shifts of carbons C3 and C6, directly bonded to iodine atoms, produced a reasonable agreement with experiment (initial deviation from experiment of 41.57 dropped to 5.6 ppm). A good linear correlation between experimental and theoretically predicted structural and NMR parameters was observed. Graphical Abstract: [Figure not available: see fulltext.]

KW - Faculty of Science

KW - ZORA

KW - NMR; chemical shift

KW - DFT calculations

KW - Relativistic Effects

KW - computational chemistry

KW - Quantum Chemistry

KW - NMR spectrocopy

KW - carbazole

U2 - 10.1007/s11224-014-0554-8

DO - 10.1007/s11224-014-0554-8

M3 - Journal article

SN - 1040-0400

VL - 26

SP - 997

EP - 1006

JO - Structural Chemistry

JF - Structural Chemistry

IS - 4

ER -