“…, 4-isocyano-2,2,6,6-tetramethylpiperidine-1-oxyl (3) (using gaseous phosgene as a reagent) [38], 4-isoselenocyanato-2,2,6,6-tetramethylpiperidine-1-oxyl 4 [39], and 1-formyl-2,2,6,6-tetramethylpiperidine (10) [37] were synthesized as described previously. A protocol for a synthesis of 4-isocyano-2,2,6,6-tetramethylpiperidine-1-oxyl (3) using diphosgene as a reagent is presented below.…”