New dirhodium(II,II) species as building corner connectors for square molecular boxes

Abstract

The new mixed dirhodium(II,II) complexes, [Rh 2(form) 2(O 2CC 6H 4CN) 2] ( 2) and [Rh 2(form) 2(O 2CC 5H 4N) 2] ( 3) (form= N, N′-di- p-tolylformamidinate) as building corner connectors for heteronuclear molecular boxes, were synthesized. By exploiting the peculiar equatorial reactivity of [Rh 2(form) 2(O 2CCF3) 2(H 2O) 2] ( 1), due to the lability of trifluoroacetates, the synthesis of 2 and 3 was readily achieved by mathematical relations with the exo-functionalized 4-cyanobenzoate and isonicotinate carboxylates, respectively. The X-ray diffraction studies performed on the pyridine adduct of 2, [Rh 2(form) 2(O 2CC 6H 4CN) 2(Py) 2], are reported, together with some preliminary attempts of self-assembly with square-planar platinum(II) and palladium(II) complexes.