Syntheses and structures of transition metal thiolate complexes containing the new bis(tetramethylguanidine) ligand btmgp

The syntheses, spectroscopic and structural characterizations of the first iron and copper thiolate guanidine complexes are described. Reactions of the neutral complexes [CuI(btmgp)] and [FeI2(btmgp)] [btmgp=1,3-bis(N,N,N′,N′-tetramethylguanidino)propane] with different uni- and bi-dentate thiolate ions yield the three-coordinate complex [Cu(S-2,4,6-tBu3C6H2)(btmgp)] (1) and the four-coordinate complexes [Fe(S-2,4,6-iPr3C6H2)2(btmgp)] (2) and [Fe(SiMe2(C6H4S)2)(btmgp)] (3) respectively. Starting with [Fe(N(SiMe3)2)2], btmgp and the dithiol SiMe2(C6H4SH)2, an alternative procedure for the preparation of 3 is reported, demonstrating a useful synthetic approach towards neutral, N/S mixed coordinated Fe(II) complexes. The X-ray structure analyses of 1–3 reveal trigonal planar (2N/1S) (1) and tetrahedral (2N/2S) (2, 3) coordination environments around the metal centers.