New supramolecular architectures based on polyfunctional organotin tetrazoles: Synthesis and characterisation of phenylene-bridged bis(organotin tetrazoles)

Seven bis(organostannyltetrazoles), R₃SnN₄C-X-CN₄SnR₃ (R = Et, Bu or Pr_i; X = 1,2-, 1,3- or 1,4-C₆H₄), have been synthesised by a cycloaddition reaction involving SnR₃N₃ and NC-X-CN. All of the products formed incorporate a trans-N₂SnC₃ stereochemistry about tin, though the co-ordination mode of the tetrazole has been found to vary in the combinations of ligating nitrogen atoms used. The crystal structure of 1,3-(2-Bu₃SnN₄C)₂C₆H ₄·2MeOH showed that the preferred co-ordination site for tin on the tetrazole is the less-hindered N² position. The crystal structures of 1,2-(2-Et₃SnN₄C)₂C₆H₄ and 1,2-(2-Bu₃SnN₄C)₂C₆H₄, respectively showed that these compounds are either two- or three-dimensional supramolecular arrays, the arrangements of which are dictated by the organic groups on tin.