The anion 2-(5-amino-3,4-dicyano-2H-pyrrol-2-ylidene) -1,1,2-tricyanoethanide (L', C11H2N7-), after isomerization to 1,2,6,7-tetracyano-3,5-dihydro-3,5-diimino-pyrrolizinide (L), forms different metal-complexes with mercury depending on the experimental conditions. Pure compounds were isolated from the reactions HL + CH3HgAc in CH3CN and NaL' + HgAc2 in AcH/H2O. They are CH,HgL and HgL2. From their optical spectra, compared to those of phthalocyaninato- or other well-known pyrrolizinato-complexes, the coordination geometry of Hg(II) in these species is supposed to be trigonal planar and trigonal monopyramidal, respectively. CH3HgL was characterized also by H-1 NMR: (CD3CN, delta, ppm) 0.886 (CH3), 8.733 (NH). From the reactions in water between NaL' and HgCl2 or HgClO4 complex mixtures of polynuclear complexes were isolated of composition: 0.826 [Hg2ClL2(OH)]. 0.174 [Hg4L3(OH)(5)]. 2.06 H2O (A) or 0.588 [Hg2L2] 0.412 [Hg2L(OH)(3)]. 3.53 H2O (B), respectively. The formulae A and B were based on thermogravimetric and elemental analysis data, Indirect evidences, based on XPS data, for the existence of the pyrrolizinato-Hg(I) complex an also given. (C) 1999 Elsevier Science Ltd. All rights reserved.
Mercury complexes with 1,2,6,7-tetracyano-3,5-dihydro-3,5-diimino-pyrrolizinide / Alberto, Flamini; Guido, Righini; Mannina, Luisa. - In: POLYHEDRON. - ISSN 0277-5387. - ELETTRONICO. - 18:6(1999), pp. 799-806. [10.1016/s0277-5387(98)00360-x]
Mercury complexes with 1,2,6,7-tetracyano-3,5-dihydro-3,5-diimino-pyrrolizinide
MANNINA, LUISA
1999
Abstract
The anion 2-(5-amino-3,4-dicyano-2H-pyrrol-2-ylidene) -1,1,2-tricyanoethanide (L', C11H2N7-), after isomerization to 1,2,6,7-tetracyano-3,5-dihydro-3,5-diimino-pyrrolizinide (L), forms different metal-complexes with mercury depending on the experimental conditions. Pure compounds were isolated from the reactions HL + CH3HgAc in CH3CN and NaL' + HgAc2 in AcH/H2O. They are CH,HgL and HgL2. From their optical spectra, compared to those of phthalocyaninato- or other well-known pyrrolizinato-complexes, the coordination geometry of Hg(II) in these species is supposed to be trigonal planar and trigonal monopyramidal, respectively. CH3HgL was characterized also by H-1 NMR: (CD3CN, delta, ppm) 0.886 (CH3), 8.733 (NH). From the reactions in water between NaL' and HgCl2 or HgClO4 complex mixtures of polynuclear complexes were isolated of composition: 0.826 [Hg2ClL2(OH)]. 0.174 [Hg4L3(OH)(5)]. 2.06 H2O (A) or 0.588 [Hg2L2] 0.412 [Hg2L(OH)(3)]. 3.53 H2O (B), respectively. The formulae A and B were based on thermogravimetric and elemental analysis data, Indirect evidences, based on XPS data, for the existence of the pyrrolizinato-Hg(I) complex an also given. (C) 1999 Elsevier Science Ltd. All rights reserved.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
