Organometallic nitrosyl chemistry. Part 3. Some aspects of the chemistry of bis[(η-cyclopentadienyl)dinitrosylchromium]

Abstract

The compound [{Cr(cp)(NO)₂}₂](cp =η-cyclopentadienyl), like its isoelectronic carbonyl analogue [{Fe(cp)-(CO)₂}₂], is cleaved by I₂, HCl(aq), and NOCl at room temperature to give [Cr(cp)(NO)₂X](X = I or Cl). However, unlike its carbonyl analogue, the chromium dimer abstracts all the chlorine ligands from SnCl₄, MCl₂(M = Hg, Sn, or Pb). [Fe(cp)(CO)₂Cl], and [Mn(CO)₅Cl] in refuxing polar organic solvents to form [Cr(cp)(NO)₂Cl]. The other products in these reactions are the metals (M), [{Fe(cp)(CO)₂}₂], and [Mn₂(CO)₁₀] respectively. Under certain conditions (such as heating in refluxing toluene) the chromium dimer is converted into [(ON)(cp) Cr(µ-NO)(µ-NH₂) Cr(cp)(NO)], whereas the related manganese dimer [{Mn(C₅H₄Me)(CO)(NO)}₂] is transformed into [Mn(C₅H₄Me)(CO)₃] and [Mn₃(C₅H₄Me)₃(NO)₄] in refluxing thf. Both these latter conversions occur in low yields.