The use of [Fe(dithiooxalate)(2)(NO)](2-) as a tecton in crystal engineering

Abstract

A series of crystalline salts based on the complex dianion [Fe(dto)(2)(NO)](2-) (dto = 1,2-dithiooxalate) with hydrogen-bond donor cations have been synthesised. The preparation and structural characterisation of the new crystalline phases [4,4'-H(2)bipy][Fe(dto)(2)(NO)]center dot H2O (1), [3,3'-H(2)bipy][Fe (dto)(2)(NO)] (2) and [H(2)Me(4)bipyz][Fe(dto)(2)(NO)]center dot 2H(2)O (3) (Me(4)bipyz = 3,3',5,5'-tetramethyl-4,4'-bipyrazole) are reported, and show that a charge-assisted NH center dot center dot center dot dto synthon is formed in each of compounds 1-3. In compound 1 the anion forms a dimer in the solid-state, and variable temperature magnetic susceptibility measurements reveal a weak antiferromagnetic interaction with a best fit superexchange parameter J = -3.18 (2) cm(-1), where H = -2JS(1)S(2).