Structural chemistry of organotin(IV) complexes

Abstract

The amazing structural diversity in organotin compounds is discussed in the systems containing -O and -S donor ligands. It is demonstrated that there exist a fascinating range of structural diversity for organotin(IV) complexes, including differences in coordination number and molecular geometry. The difference in structure is correlated with the nature of tin and ligand bonded R groups. Despite the large number of different structures found in organotin(IV) carboxylates, there is limited range of coordination geometries about the Sn atom. The four coordinated Sn atom in triorganotin(IV) complexes is invariably distorted tetrahedral and five coordinated Sn is distorted trigonal bipyramidal. A large range has been observed for diorganotin carboxylate structures, where five, six and seven coordinate geometries have been reported. The Sn atom in mono-organotin has only been demonstrated to exist in distorted octahedral geometries (the single exception being a pentagonal bipyramidal geometry). In the case of organotin(IV) complexes of S donor ligands, it has been shown that there exists a rich diversity in Sn atom geometries and coordination modes of the sulfur donor ligands themselves. As in related carboxylate systems, the assignment of coordination numbers to the Sn centers in some compounds is controversial. As a general trend, it has been shown that, the overall coordination number at the Sn atom decreases with the increasing number of organic substituents at the Sn atom. This phenomenon is usually achieved by increased asymmetry in the mode of coordination of the sulfur donor ligands.

Synthesis, characterization and antimicrobial activities of organotin(IV) complexes with ethylthioglycolate

“…Compounds 1-4 are four-coordinated with distorted tetrahedral geometry, in which Sn atom is attached to S atom of ethylthioglycolate. All bond angles and bond lengths are closer to those reported in literature (Shahzadi and Ali. 2008).…”

Synthesis and characterization of some new di- and triorganotin(IV) complexes of Schiff base derived from o-vanillin and acetazolamide using microwaves

“…The stability and structural diversity of organotin compounds make their coordination chemistry very interesting, and their extensive use in various fields of life results in a quantum leap of organotin chemistry (Omae, 1989;Davies, 2004;Shahzadi and Ali, 2008;Nath and Saini, 2011). One of the most rapidly developing areas of pharmaceutical research is the discovery of robust drugs for treating cancer.…”

Diorganotin(IV) Complexes with Monohydrate Disodium Salt of Iminodiacetic Acid: Synthesis, Characterization, Crystal Structure and Biological Activities

“…1 Information on the structures of organotin(IV) carboxylates continues and a large range has been observed for the structures of diorganotin carboxylates, where five, six and seven coordinate geometries have been reported. 4 Among diorganotin(IV) bis(carboxylates), the coordination geometry around the Sn atom is usually found to be skew trapezoidal. 5 In such a kind of structural motif, the Sn atom is hexa-coordinated and the carboxylate ligand chelates the Sn atom, forming disparate Sn-O bond distances.…”

“…[1][2][3][4] Coordination of carboxylate to metals in general and to organotin residues in particular offers the possibility of studying the variations in coordination modes which include monodentate, chelate (symmetric or more often asymmetric) or the more subtle bridging mode which may give rise to oligomeric or polymeric structures. 1 Information on the structures of organotin(IV) carboxylates continues and a large range has been observed for the structures of diorganotin carboxylates, where five, six and seven coordinate geometries have been reported.…”