Interaction of Methylmercury(II) with Bidentate Ligands Containing Pyridine and Pyrazole Rings. Synthesis and Structure of Methyl[l-(2-pyridyl)pyrazole]mercury(II) Nitrate and [Di(1-pyrazolyl)methane]methylmercury(II) Nitrate

The complexes [MeHgL]N03[L = 1-(2-pyridyl)pyrazole or di(1-pyrazolyl)methane] have L present as bidentate ligands to give irregular three coordination for Hg in the CHgN2 moieties. The 1-(2-pyridyl)pyrazole complex has C(1)-Hg-N(1) 168(2)° and Hg-N(1) 2,21(3) A [N(1) is the pyrazole donor atom], Hg-N(1')(pyridine ring) 2,61(5) A, and nitrate oxygen atoms 2,97(3), 3,07(3), and 3,14(3) Afrom Hg. The di(l-pyrazolyl)methane cation complex has C(1)-Hg-N(1) 179(1), Hg-N(1) 2,16(1), Hg-N(1') 2,96(2) A, and nitrate oxygen atoms 2,88(2)and 2,90(2) A from Hg. In both structures the cations and anions are grouped to form [MeHgL]NO3 dimeric units via Hg...O interactions.