Comparison of nucleophilic- and radical-based routes to the formation of manganese-main group element single bonds.

Abstract

Using the stable metalloradical Mn(CO)3(CNArDipp2)2, we report the formation of manganese-main group complexes via the single-electron functionalization of main group halides. The reactions occur in a simple 1 : 1 stoichiometry, and demonstrate the utility of using stable open-shelled organometallics as precursors for metal-main group compounds. This has enabled the preparation of manganese complexes bearing terminal -EXn substituents, as shown through the isolation of Mn(SnCl)(CO)3(CNArDipp2)2 and Mn(BiCl2)(CO)3(CNArDipp2)2 from SnCl2 and BiCl3, respectively. Through this approach, we have also isolated Mn(SbF2)(CO)3(CNArDipp2)2 from SbF3, which serves as a unique example of a terminal -SbF2 complex. Although the metalloradical functionalization of binary main group halides provides the desired main group adduct in yields comparable to nucleophilic activation using the manganate Na[Mn(CO)3(CNArDipp2)2], the former approach is shown to be far more atom-economical with respect to Mn. Additionally, we have found that Mn(CO)3(CNArDipp2)2 also serves as a convenient precursor to MnF(CO)3(CNArDipp2). The latter is an analogue to the elusive monofluoride FMn(CO)5.