Two coordination compounds of SnCl 2 with 4-methylpyridine N -oxide

In the solid-state structures of catena -poly[[dichloridotin(II)]-μ 2 -(4-methylpyridine N -oxide)-κ 2 O : O ], [SnCl 2 (C 6 H 7 NO)] n , 1 , and dichloridobis(4-methylpyridine N -oxide-κ O )tin(II), [SnCl 2 (C 6 H 7 NO) 2 ], 2 , the bivalent tin atoms reveal a seesaw coordination with both chlorine atoms in equatorial and the Lewis base molecules in axial positions. While the Sn—Cl distances are almost identical, the Sn—O distances vary significantly as a result of the different bonding modes (μ 2 for 1 , μ 1 for 2 ) of the 4-methylpyridin- N -oxide molecules, giving rise to a one-dimensional coordination polymer for the 1:1 adduct, 1 , and a molecular structure for the 1:2 adduct, 2 . The different coordination modes also influence the bonding parameters within the almost planar ligand molecules, mostly expressed in N—O-bond lengthening and endocyclic bond-angle widening at the nitrogen atoms. Additional supramolecular features are found in the crystal structure of 2 as two adjacent molecules form dimers via additional, weak O...Sn interactions.