Homoleptic triorganotin(IV) organoselenolates of type R3Sn(SeCH2CH2pz)

The homoleptic triorganotin(IV) compounds of type R3Sn(SeCH2CH2pz) [R = Me (1), nBu (2), Bn (3), Ph (4); pz = pyrazole] were obtained by NaCl elimination in the reaction between Na[SeCH2CH2pz] and the appropriate triorganotin(IV) chloride. All compounds were structurally investigated in solution by multinuclear NMR (1H, 13C, 77Se, 119Sn) and APCI+ mass spectrometry. The NMR spectra suggested the equivalence of the three organic groups attached to tin, as well as the existence of the Se−Sn bonds in solution. The crystal and molecular structure of compound 4 was determined by single-crystal X-ray diffraction. The structure revealed a monodentate behaviour of the organoselenolato ligand, and a distorted tetrahedral coordination geometry about tin. H···N intermolecular interactions resulted in dimeric associations, while further π CH···Cg secondary bonding lead to a 3D supramolecular network.