Structural Consequences of S → Se Substitution in some Symmetrical [M(S₂CNR₂)₃] Complexes

Abstract

The consequences of replacement of the symmetrically chelate ligands in [M(E2CNR2)3] (E = S, Se) complexes of potential 32 symmetry by analogous mixed S,Se unsymmetrical chelates are explored for both small (M = Co) and large (M = In) metal atoms, and R = primary (Et) and secondary (iPr) alkyl substituents by way of low‐temperature single crystal X‐ray studies of [(Co(SSeCNEt2)3] ([Co(Se2CNEt2)3] also determined as datum), and [In(SSeCNR2)3], R = Et, iPr. The structure of [(iPr2N·CS·Se)2] is also recorded.

Molecular and supramolecular chemistry of mono- and di-selenium analogues of metal dithiocarbamates

“…The two known octahedral indium(III) structures, In(Se2CNR2)3 for R = Et (36) [68], Fig. 16, and i-Pr (37) [36] conform to those found for the monoselenothiocarbamates described in 2.4 and by implication to Co(SeSCNEt2)3 (6) [36] illustrated in Fig. 4.…”

“…From symmetry, the disposition of the thione-S atoms is anti. The molecular structures of the R = Et (2) [35] and i-Pr (3) [36] compounds follow the same trends, Table 1, but, each is disposed about a centre of inversion with the central N(S=)CSe-SeC(=S)N moiety being essentially planar. The exceptional structure is found when R = Cy (4) [35].…”

“…The structure of Co(Se2CNEt2)3 (13) [36] is isostructural with Co(SeSCNEt2)3 (6) [36] shown in Fig. 4 but, obviously does not display analogous positional disorder.…”

“…There are four X-ray structures conforming to the general formula [R2NC(=S)Se]2, 1-4 [13,35,36] with the R = Me (1) compound illustrated in Fig. 1.…”

“…The generally symmetric tris(ligand) structures of cobalt(III), 6 and 13, and those of indium(III), 10, 11, 36 and 37, form an interesting series of compounds that has attracted considerable attention in terms of the adopted symmetry in the solid-state [36]. The common feature of the cobalt(III) structures with R = Et is that they crystallise in the C2/c space group and are isostructural with the dithiocarbamate analogue [81]; the molecules are 2-fold symmetric.…”