Polystannanes oligostannanes

Polystannanes would be expected to possess even more o-delocalised structures, as suggested by studies of linear oligostannanes with up to six tin... 

Several cyclic and polycyclic oligostannanes with a rich structural diversity have been reported in the literature16,21 83 and it was concluded by Sita21 that the concepts and strategies established in organic chemistry can successfully be applied for the construction of polystannane frameworks as well. The polycyclic oligostannanes 16-19 are representative examples for this class of compounds. 

Currently, there is growing interest in polymers the frameworks of which are constructed from the Group 14 elements silicon, germanium and tin. Several reviews on polysilanes have appeared in the literature . In the first section of this article we focus on recent developments in the chemistry of polygermanes and polystannanes. The chemistry and structure-property relationship of oligostannanes and low molecular weight polystannanes was the subject of earlier reviews . ... 

The cyclic oligostannanes are an important class of compounds, synthesized in a similar manner to the Snj units above [53], Larger R groups lead to lower degrees of association and the formation of isolated of RjSn stannylene units and doubly bonded dimers discussed below. In terms of reaction chemistry, the principtil modes of reactivity of oligo- and polystannanes are through oxidative or reductive cleavage of Sn-Sn bonds [37]. 

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