Synthesis and Characterization of Quasi-Two-Coordinate Transition Metal Dithiolates M(SAr*)<sub>2</sub> (M = Cr, Mn, Fe, Co, Ni, Zn; Ar* = C<sub>6</sub>H<sub>3</sub>-2,6(C<sub>6</sub>H<sub>2</sub>-2,4,6-Pr<sup>i</sup><sub>3</sub>)<sub>2</sub>
收藏资源简介：
A sequence of first row transition metal(II) dithiolates M(SAr*)2 (M = Cr(1), Mn(2), Fe(3), Co(4), Ni(5) and Zn(6); Ar* = C6H3-2,6-(C6H2-2,4,6-Pri3)2) has been synthesized and characterized. Compounds 1−5 were obtained by the reaction of two equiv of LiSAr* with a metal dihalide, whereas 6 was obtained by treatment of ZnMe2 with 2 equiv of HSAr*. They were characterized by spectroscopy, magnetic measurements, and X-ray crystallography. The dithiolates 1, 2, and 4−6 possess linear or nearly linear SMS units with further interactions between M and two ipso carbons from C6H2-2,4,6-Pri3 rings. The iron species 3, however, has a bent geometry, two different Fe−S distances, and an interaction between iron and one ipso carbon of a flanking ring. The secondary M−C interactions vary in strength in the sequence Cr2+ ≈ Fe2+ > Co2+ ≈ Ni2+ > Mn2+ ≈ Zn2+ such that the manganese and zinc compounds have essentially two coordination but the chromium and iron complexes are quasi four and three coordinate, respectively. The geometric distortions in the iron species 3 suggested that the structure represents the initial stage of a rearrangement into a sandwich structure involving metal-aryl ring coordination. The bent structure of 3 probably also precludes the observation of free ion magnetism of Fe2+ recently reported for Fe{C(SiMe3)3}2. DFT calculations on the model compounds M(SPh)2 (M = Cr−Ni) support the higher tendency of the iron species to distort its geometry.
