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Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
15N solid-NMR and X-ray diffraction studies of N-confused porphyrins
Masashi Fukuchi1, K Takegoshi, Tomoya Ishizuka
1Department of Chemistry, Graduate School of Science, Kyoto University, Kyoto, Japan.
Abstract:
Using (15)N high-resolution solid-state NMR and X-ray diffraction, the structure of N-confused porphyrin (NCP) in the solid state was studied. A 1D (15)N magic angle spinning (MAS) experiment and a 2D dipolar assisted rotational resonance (DARR) (15)N-(15)N spin exchange experiment of N-confused tetratolylporphyrin (Tol) crystallized from CH(2)Cl(2)/hexane indicate that Tol is the inner 3H-type tautomer and has two magnetically different molecules in the unit cell. Further, a FSLG-2 & 4macr; 2 (1)H-(15)N dipolar recoupling NMR measurement indicates no fast ring flipping motion which is consistent with the planar structure in the X-ray analysis. The planarity of Tol is ascribed to crystal packing enforced by pi-pi stacking and CH-pi interactions.
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