The reaction of azide ions, N3-, with metal carbonyl compounds;: an electrospray mass spectrometry study

Mono- and poly-nuclear metal carbonyls, and substituted analogues, have been analysed in the presence of N-3(-) ions by negative-ion electrospray mass spectrometry. Most complexes yield the appropriate isocyanate-containing anions by conversion of a CO ligand to an NCO- one with elimination of N-2. In some cases [M + N-3](-) ions are observed; for species such as H2Os3(CO)(10) or Ru5C(CO)(15) these arise from addition at a metal-metal bond, but in other cases they may represent the first-formed adduct from attack of N-3(-) at a CO ligand. For hydride-containing clusters such as H4Ru4(CO)(12), the azide ion can act as a base, abstracting H+ and forming [M-H](-) ions in competition with nucleophilic attack. (C) 1999 Elsevier Science S.A. All rights reserved.