title: Synthesis, solid-state NMR, and X-ray powder diffraction characterization of group 12 coordination polymers, including the first example of a C-mercuriated pyrazole.
abstract: Cadmium and mercury acetates have been reacted with pyrazole (Hpz) and 3,5-dimethylpyrazole (Hdmpz), affording distinct mixed-ligand species, selectively prepared upon slightly modifying the reaction conditions. Two polymorphs of [{Cd(mu-ac)2(Hpz)2}n], as well as the [{Cd(mu-ac)2(Hdmpz)2}n] species (Hac = acetic acid), were obtained by solution chemistry, while the two-dimensional [{Cd3(mu3-ac)4(mu-pz)2(Hpz)2}n] and [{Cd(mu-ac)(mu-pz)}n] polymers were prepared upon controlled thermal treatment of one of the [{Cd(mu-ac)2(Hpz)2}n] forms. Two mercury derivatives, [{Hg3(mu-ac)3(mu-pz)3}n] and [{Hg(ac)(mu-dmpz)}n], were also prepared, the latter containing one-dimensional chains of Hg(II) ions bridged by C-mercuriated Hdmpz ligands. All their crystal structures (but one) were determined by powder diffraction methods using conventional X-ray laboratory equipment, supported by 13C CPMAS NMR measurements. The latter method helped in assigning a C-metalated nature to an amorphous material of [Hg(ac)(pz)] formula, obtained by employing EtOH as a solvent. A few other Hdmpz-containing cadmium acetates were also prepared, but their polyphasic nature, evidenced by diffraction methods, hampered their complete structural characterization.
authors.affiliation: Dipartimento di Scienze Chimiche e Ambientali, Università dell'Insubria, via Valleggio 11, 22100 Como, Italy. norberto.masciocchi@uninsubria.it
authors.forename: Norberto
authors.initials: N
authors.lastname: Masciocchi
authors.forename: Simona
authors.initials: S
authors.lastname: Galli
authors.forename: Enrica
authors.initials: E
authors.lastname: Alberti
authors.forename: Angelo
authors.initials: A
authors.lastname: Sironi
authors.forename: Corrado
authors.initials: C
authors.lastname: Di Nicola
authors.forename: Claudio
authors.initials: C
authors.lastname: Pettinari
authors.forename: Luciano
authors.initials: L
authors.lastname: Pandolfo
mesh_terms: D002104:Cadmium / Q000737:chemistry*; D018360:Crystallography, X-Ray; D009682:Magnetic Resonance Spectroscopy; D008628:Mercury / Q000737:chemistry*; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D011108:Polymers / Q000138:chemical synthesis / Q000737:chemistry; D011720:Pyrazoles / Q000138:chemical synthesis / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D009942:Organometallic Compounds; D011108:Polymers; D011720:Pyrazoles; D002104:Cadmium; D008628:Mercury