Abstract

1.The reaction of PhHgOAc with N–NHCO-2-C4H3S-Htpp (5) and N–p-HNSO2C6H4tBu-Htpp (4) gave a mercury (II) complex of (phenylato) (N-2-thiophenecarboxamido-meso-tetra phenylporphyrinato)mercury(II) 1.5 methylene chloride solvate [HgPh(N–NHCO-2-C4H3S-tpp)•CH2Cl2•0.5C6H14; 6•CH2Cl2•0.5C6H14] and a bismercury complex of bisphenylmercury(II) complex of 21-(4-tert-butyl-benzenesulfonamido)-5,10,15,20,- tetraphenylporphyrin, [(HgPh)2 (N–p-NSO2C6H4tBu-tpp); 7], respectively. The crystal structures of 6•CH2Cl2•0.5C6H14 and 7 were determined. The coordination sphere around Hg(1) in 6•CH2Cl2•0.5C6H14 and Hg(2) in 7 is a sitting-atop derivative with a seesaw geometry, whereas for the Hg(1) in 7, it is a linear coordination geometry. Both Hg(1) in 6•CH2Cl2•0.5C6H14 and Hg(2) in 7 acquire 4-coordination with four strong bonds [Hg(1)-N(1) = 2.586(3) A, Hg(1)-N(2) = 2.118(3) A, Hg(1)-N(3) = 2.625(3) A, and Hg(1)-C(50) = 2.049(4) A for 6•CH2Cl2•0.5C6H14; Hg(2)-N(1) = 2.566(6) A, Hg(2)-N(2) = 2.155(6) A, Hg(2)-N(3) = 2.583(6) A, and Hg(2)-C(61) = 2.064(7) A for 7]. The plane of the three pyrrole nitrogen atoms [i.e., N(1)-N(3)] strongly bonded to Hg(1) in 6•CH2Cl2•0.5C6H14 and to Hg(2) in 7 is adopted as a reference plane 3N. For the Hg2+ complex in 6•CH2Cl2•0.5C6H14 , the pyrrole nitrogen bonded to the 2-thiophenecarboxamido ligand lies in a plane with a dihedral angle of 33.4° with respect to the 3N plane, but for the bismercury(II) complex in 7, the corresponding dihedral angle for the pyrrole nitrogen bonded to the NSO2C6H4tBu group is found to be 42.9°. In the former complex, Hg(1)2+ and N(5) are located on different sides at 1.47 and -1.29 A from its 3N plane, and in the latter one, Hg(2)2+ and N(5) are also located on different sides at -1.49 and 1.36 A form its 3N plane. The Hg(1)•••Hg(2) distance in 7 is 3.622(6) A. Hence, no metallophilic Hg(II)•••Hg(II) interaction may be anticipated. NOE difference spectroscopy, HMQC and HMBC were employed to unambiguous assignment for the 1H and 13C NMR resonances of 6•CH2Cl2•0.5C6H14 in CD2Cl2 and 7 in CDCl3 at 20°C. The 199Hg chemical shift δ for a 0.05 M solution of 7 in CDCl3 solution is observed at -1074 ppm for Hg(2) nucleus with a coordination number of four and at -1191 ppm for Hg(1) nucleus with a coordination number of two. The former resonance is consistent with that chemical shift for a 0.01 M solution of 6 in CD2Cl2 having observed at -1108 ppm for Hg(1) nucleus with a coordination number of four. 2.The crystal structures of diamagnetic N-p-tert-butylbenzenesulfonylimido- meso-tetraphenylporphyrinatonickle(II) [Ni(N-p-NSO2C6H4tBu-tpp); 8] and paramagnetic acetato-[N-p-tert-butylbenzenesulfonylimido-meso- tetraphenylporphyrinato]manganese(III) [Mn(N-p-NSO2C6H4 tBu-tpp)(O2CCH3); 9] were determined. The coordination sphere around Ni2+ in 8 is described as four-coordinated distorted square planar, whereas, for the Mn3+ ion in 9, it is a five-coordinate distorted square-based pyramid in which the unidentate CH3COO- ligand occupied the axial site. By the ‘‘degree of trigonality’’ principle ,the penta-coordinated Mn(III) complex is best described as a distorted trigonal bipyramid (or a squarebased pyramidal distorted trigonal bipyramid, SBPDTBP) The magnetic moment of 9 clearly shows a plateau equal to 4.57 µB, which is close to the expected value of 4.90 µB for a quintet high-spin state (S = 2).The g value of 12.6 (or 8.8) measured from the parallel polarization (or perpendicular polarization) of X-band EPR spectra at 77 K is consistent with a high spin manganese(III) (S = 2) in 9. The magnitude of axial (D) zero-field splitting (ZFS) in 9 were determined approximately as –1.1 cm-1, by paramagnetic susceptibility measurements and EPR spectroscopy.

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