Linear polystannanes structure

Relatively few linear polystannanes have been the subject of crystallographic analysis Table IV and Fig. 4 provide some selected structural... 

Emax = 13 690) of compound 2 was similar to that previously observed fbr short-chain linear polystannanes [5], an oligomeric polystatmane structure with Sn-Sn a-delocalization was assumed. Indeed, as shown in Figure 2, crystallographic analysis revealed that the molecular structure of 2 possesses six tin atoms arranged in a bicyclo[2.2.0]hexane framework comprised of a cis fusion... 

Most of the reactions that can be used to prepare distannanes can be extended to the preparation of oligo- and polystannanes, which have attracted interest for potential use in electronic and optical devices.455 The structures of the products are not necessarily those of completely linear catenanes, (R2Sn) , and different degrees of branching confer different properties. The formation of polymers is also frequently accompanied by the formation of cyclic pentamers or hexamers, and samples prepared by different methods may show substantially different properties. 

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

Polystannanes are routinely characterized by and spectroscopy, and (GPC) against polystyrene standards of different molecular weights in THF. However, it is often " Sn NMR in particular that is a valuable tool to determine the structure of the linear oligomeric and polymeric chains and provides useful information regarding purity of polymer chains and ratios and types of cyclic oligomers. 

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