1. Several azines containing a bistrifluoromethylamino-oxy group as a side-chain component are known, e.g., 4-(CF3)2NOCH2·C5F4N {from 4-CH3·C5F4N + (CF3)2NO· [R.E. Banks, R.N. Haszeldine and G. Shaw, unpublished results (see G. Shaw, Ph.D. Thesis, University of Manchester, 1968)]}, 3-(CF3)2NOCH2·C5H4N {from 3-CH3·C5H4N + (CF3)2NO· [R.E. Banks, R.N. Haszeldine and R.A. Hughes, unpublished results]}, and 2-(CF3)2NOC(O)·C5H4N {from 2-HOCH2·C5H4N or 2-HC(O)·C5H4N + (CF3)2NO· [R.E. Banks, R.N. Haszeldine, R.A. Hughes, C.M. Irvin, and A.E. Tipping, unpublished results (see C.M. Irvin, Ph.D. Thesis, University of Manchester, 1980)]}.
2. R.E. Banks, R.N. Haszeldine, R.A. Hughes, C.M. Irvin and A.E. Tipping, unpublished results.
3. Prepared by shaking mercury with a two-molar equivalent of bistrifluoromethyl nitroxide at 20 °C for 2 h, followed by removal of the unreacted radical (in vacuo) from the reaction vessel (Pyrex ampoule) after it had been kept in the dark at room temperature for 12 h; the chlorinated substrate under investigation and the solvent were then distilled into the ampoule using vacuum transference procedures; the ampoule was fitted with a PTFE needle valve (4 mm Rotaflo) to facilitate the manipulations required. Details of the preparation of mercurials of composition [(CF3)2NO]2Hg [5] and (CF3)2NOHg [6] can be found in the literature; production of the mercury (II) derivative requires the use of at least a threefold excess of bistrifluoromethyl nitroxide [7] and preferably [5] a 10:1 (CF3)2NO·: Hg stoicheiometry — a costly business. Note that an upper temperature limit of ca. 50 °C must be imposed on reactions involving these mercurials to restrict their dissociation, which occurs cleanly and efficiently in the range 65 – 85 °C [5,6] and provides the basis for a method of purification of bistrifluoromethyl nitroxide [6].
4. Preparation and reactions of mercury(II) bistrifluoromethylnitroxide