Jyh-Horung Chen

Molecular structure of thallium(III) meso-tetraphenylporphyrin acetate: Tl(tpp)(OAc)

Abstract X-ray diffraction data and solid-state 13C CP/MAS spectra of thallium(III) mesotetraphenylporphyrin acetate, Tl(tpp)(OAc), provide evidence for a chelating-bidentate acetato group coordinated to the thallium(III) atom. The displacement of the thallium atom from the porphyrin mean plane was 0.842 A. The geometry around the thallium centre of the Tl(tpp)(OAc) molecule has TlO(1) = 2.361(9), TlO(2) = 2.229(10) and TlN = 2.219(7) A. Fourier-transform IR spectra (400–4000 cm−1) of Tl(tpp)(OAc) in KBr discs and in CH2Cl2 solvent are reported and assigned by comparison with the spectra of Tl(tpp)(CN). It is concluded that the intramolecular exchange of the acetato group between asymmetric pseudo-chelating c and d result in the adaptation of the chelating bidentate, a for the carboxylate at low temperature and that of the symmetric pseudochelating b at high temperature for Tl(tpp)(OAc) in CH2Cl2 solvent. This explains the resonances of 13C and 1H of the axial acetato group in low- and high-temperature solution NMR measurements.

Unusual Inner C‑Alkylation of 2‑N-Substituted N‑Confused Porphyrin Cobalt Complexes in Toluene and p‑Xylene

The inner C-benzyl- and C-p-xylyl-substituted cobalt(II) complexes of a 2-N-substituted N-confused porphyrin were synthesized from the reaction of 2-NCH2COOCH2C6H5NCTPPH (1) and CoCl2·6H2O in toluene (or p-xylene), and the structures were revealed by single-crystal X-ray analysis.

Synthesis and molecular structure of meso-tetra(4-pyridyl) porphyrinatothallium(III) cyanide : Tl(tpyp)(CN)

Abstract The new compound meso-tetra(4-pyridyl) porphyrinatothallium(III) cyanide, Tl(tpyp)(CN), has been synthesized and its molecular structure determined by X-ray analysis. The thallium-carbon(cyanide) distances are 2.163 (12) A [for thallium (1)] and 2.121 (28) A [for thallium (2)], respectively, with thallium(1) situated 0.825 A above the porphyrin ring and thallium(2) located 0.900 A below the ring. The characteristic band observed at 2163 cm−1 in the FTIR spectrum confirms that the CN group is present in the Tl(tpyp)(CN) complex. The 13C resonance of the axial cyano ligand was observed at 137.7 ppm (24°C) (with 1J(205Tl-13C) coupling constant 5852 Hz and 1J(203Tl-13C) coupling constant 5795 Hz). The Correlation Spectroscopy via Long-Range Coupling technique (COLOC) was used to resolve two quaternary carbons ie. Cα and C-1 at 149.3 and 149.1 ppm, respectively.