1: With 1,10-phenanthroline; potassium carbonate; copper(I) bromide; diethylazodicarboxylate in toluene T=20°C; 0.25 h; 2: With oxygen in toluene T=90°C; P=760.051 Torr; 1.5 h; chemoselective reaction;

4-acetylamino 2,2,6,6-tetramethylpiperidin-N-oxyl; nitric acid; sodium nitrite in water; acetic acid T=20°C; P=760.051 Torr; 12 h;

1.1: potassium carbonate / acetonitrile 2.1: lithium diisopropyl amide / tetrahydrofuran 2.2: -78 - 20 °C 3.1: sodium tetrahydroborate / tetrahydrofuran; water 4.1: 4-acetylamino 2,2,6,6-tetramethylpiperidin-N-oxyl; nitric acid; sodium nitrite / water; acetic acid / 12 h / 20 °C / 760.05 Torr View Scheme

1.1: lithium diisopropyl amide / tetrahydrofuran 1.2: -78 - 20 °C 2.1: sodium tetrahydroborate / tetrahydrofuran; water 3.1: 4-acetylamino 2,2,6,6-tetramethylpiperidin-N-oxyl; nitric acid; sodium nitrite / water; acetic acid / 12 h / 20 °C / 760.05 Torr View Scheme

1: sodium tetrahydroborate / tetrahydrofuran; water 2: 4-acetylamino 2,2,6,6-tetramethylpiperidin-N-oxyl; nitric acid; sodium nitrite / water; acetic acid / 12 h / 20 °C / 760.05 Torr View Scheme

1.1: 4-acetylamino 2,2,6,6-tetramethylpiperidin-N-oxyl; oxygen; nitric acid; hydrogenchloride / water; acetonitrile / 24 h / 45 °C / |High pressure; |Sealed tube 2.1: lithium diisopropyl amide / tetrahydrofuran 2.2: -78 - 20 °C 3.1: sodium tetrahydroborate / tetrahydrofuran; water 4.1: 4-acetylamino 2,2,6,6-tetramethylpiperidin-N-oxyl; nitric acid; sodium nitrite / water; acetic acid / 12 h / 20 °C / 760.05 Torr View Scheme

1.1: lithium diisopropyl amide / tetrahydrofuran 1.2: -78 - 20 °C 2.1: sodium tetrahydroborate / tetrahydrofuran; water 3.1: 4-acetylamino 2,2,6,6-tetramethylpiperidin-N-oxyl; nitric acid; sodium nitrite / water; acetic acid / 12 h / 20 °C / 760.05 Torr View Scheme