Synthesis, Structure and Magnetic Behaviour of Manganese(II) Selenolate Complexes _∞¹[Mn(SePh)₂], [Mn(SePh)₂(bipy)₂] and [Mn(SePh)₂(phen)₂] (bipy = bipyridyl, phen = phenanthroline)

Abstract

The manganese selenolate complex ϱ 1 [Mn(SePh) 2 ] has been prepared by reaction of Mn(OOCCH 3 ) 2 with 2 equiv. PhSeSiMe 3 in thf. In the crystal structure, the compound forms one-dimensional chains, and the bridging selenolate ligands result in relatively short metal-metal contacts of about 3 Å. Reaction with two equivalents of the Lewis bases

1‐D Polymeric Iron(II) Thiolato Complexes: Synthesis, Structure, and Properties of ∞1[Fe(SR)2] (R = Ph, Mes), ∞1[Fe(NH3)(SPh)(µ‐SPh)] and ∞1[(µ‐SPh)Fe(NH3)2(µ‐SPh)2Fe(µ‐SPh)]

“…Complex 2 displays a broad maximum in the temperature dependence of χ centered around 75 K which is characteristic for strong antiferromagnetic exchange in the chain. A similar behavior has been recently observed for the related chain compounds ∞ 1 [M(SMes) 2 ] (M = Mn,Co) and ∞ 1 [M(SeMes) 2 ] (M = Mn, Fe). The curve has been fitted for the data between 50 and 300 K by both the classical approximation used by Fisher (eqn S1, SI) which is expected to be good for large moments, and the approach of Bonner and Fisher, expanded by Weng,, (eqn S2, SI) which should be more appropriate for smaller, quantum spin systems.…”

“…At temperatures below 70 K the experimental curve deviates from the model in two characteristic ways which have been also observed for the above mentioned related complexes of general formula ∞ 1 [M(EMes) 2 ] (M = Mn, Fe, Co; E = S, Se) , , , . The decrease of χ is more rapid (steep) and there is a second increase of χ at low temperatures.…”

Trinuclear Early/Late‐Transition‐Metal Thiolate Complexes

“…An almost linear behaviour of the χ -1 versus T plot of 1 (Figure S8) below 125 K and a small negative Weiss constant (-4.9 K) derived from a fit of it suggest that the compound behaves nearly as an ideal paramagnet in this temperature region, which, together with a small Curie constant (2.56 cm 3 mol -1 K), is indicative of a very strong antiferromagnetic exchange of the three S = 3/2 ions in 1. This is in agreement with findings on homoleptic 1D manganese and iron selenolate complexes [52] Fe [53] ) in which we found that acute μ 2 -selenolate bridges (MnSe-Mn and Fe-Se-Fe: 71.15-72.57°) lead to a very strong antiferromagnetic superexchange between the paramagnetic ions. As expected, upon going to higher temperature above 150 K, increasingly higher-lying spin states are populated, which results in a slight increase in the curve of μ eff versus T. The magnetic behaviour of 3 is different to that of 1 and 2 ( Figure 6).…”

Polymeric cobalt(ii) thiolato complexes – syntheses, structures and properties of 1∞[Co(SMes)2] and 1∞[Co(SPh)2NH3]

“…ring-like) or polymeric structures. Examples for transition metals include the oligomeric ring structures of [{Ni(μ-SPh) 2 } n ] (n = 9, 11), 20 [{Ni(μ-S i Pr)(μ-mtet)} 6 ], [{Ni(μ-S t Bu) (μ-mtet)} 10 ] (mtet = 2-methylthioethanethiolate) 21 and [{Fe(SePh) 2 } 12 ], 22 the 1D chain structures of 1 1 [M(SeR) 2 ] (M = Mn, Fe; R = Ph, Mes; Mes = C 6 H 2 -2,4,6-(CH 3 ) 3 ) [23][24][25] and the 3D adamantoid network structure of 3 1 [Zn 4 (SPh) 8 CH 3 OH], 26 28 In this respect dimeric [{Co(SR) 2 } 2 ] (R = 2,4,6-t Bu 3 C 6 H 2 ) and hexameric [{Co(SEt) 2 } 6 ] (Et = C 2 H 5 ) are the only polynuclear examples for cobalt which have been characterized by single crystal X-ray diffraction. 29 In contrast a few more homoleptic thiolato complexes of cobalt which are ionic have been structurally characterized including the above mentioned [Co(SPh) 4 ] 4− , 30 33 The latter ones can be viewed as structural building blocks of oligomeric and polymeric structures mentioned above.…”