Synthesis, structure, optical, and thermal properties of diallylammonium hexabromostannate(IV) hybrid

Diallylammonium hexabromostannate(IV) was synthesized and characterized by IR, 1H, 13C NMR, DRS, TG-DTA, Single crystal XRD. 1H chemical shifts of the protons in the hybrid are lower than the diallylammonium cation due to extensive hydrogen bonded and weak van der Waals interactions. The NH 2 + protons of the hybrid are observed as a singlet at 8.963 ppm compared to those of the diallylammonium chloride at 9.800 ppm, a significant decrease. 13C NMR spectrum shows a maximum downward chemical shift for α-C(H2). DRS spectrum shows a strong charge transfer transition in the range 429 to 492 nm.The hybrid is thermally stable up to ∼195°C. Single crystal X-ray crystallography shows the asymmetric unit to be [C 6 H 12 N] + 0.5[SnBr 6 ] 2−. All the bromide ions are involved in hydrogen bonding. BVS of tin in diallylammoniumhexabromostannate(IV) was calculated based on the Sn-Br bond distances obtained from the single crystal X-ray structural analysis as 3.941, which is close to its formal oxidation state of +4. This is the first report which clearly established the formal oxidation state of tin in a hybrid material from X-ray structural data. The CSM of SnBr 6 2− anion was found to be 0.0145 indicating its near perfect octahedral geometry.