Carbonyl dihalides: synthesis and spectroscopic characterization

Abstract

New, or improved, syntheses of phosgene, carbonyl bromide chloride and carbonyl bromide fluoride have been elaborated. The NMR ( ¹³ C, ¹⁹ F and ¹⁷ O) and electron impact mass spectra were recorded for COX ₂ (X = F, Cl or Br), COClF, COBrCl and COBrF; trends in the chemical shifts are analysed in terms of σ and π contributions to the bonding. Attempts to prepare carbonyl diiodide in solution were unsuccessful, and the reasons for this are analysed.