[OH:1][N:2]1[C:7]([CH3:9])([CH3:8])[CH2:6][CH:5]([OH:10])[CH2:4][C:3]1([CH3:12])[CH3:11].[C:13](#N)[CH3:14].Cl.OO>O.[Fe].C1CCCCC1>[CH:14]1([O:1][N:2]2[C:7]([CH3:8])([CH3:9])[CH2:6][CH:5]([OH:10])[CH2:4][C:3]2([CH3:12])[CH3:11])[CH2:13][CH2:5][CH2:4][CH2:3][CH2:11]1
Nanosized activated iron powder in mineral oil (0.042 g) is rinsed successively with two 2 ml portions of cyclohexane. Most of the solvent is removed with a pipette. The iron is added to a mixture of 5.00 g (29.0 mmol) of 1-oxyl-2,2,6,6-tetramethylpiperidin-4-ol, 44 ml of acetonitrile, and 32 ml of cyclohexane that has been heated to 40 degrees. To this mixture is carefully added over several minutes a solution of 0.548 g of concentrated hydrochloric acid in 3 ml of water. The reaction temperature is brought to reflux and a solution of 7.81 g (115 mmol) of 50% aqueous hydrogen peroxide is added dropwise over a period of 2.25 hours. After about one-half of the peroxide solution is added, a second portion of nanosized activated iron powder in mineral oil (0.039 g), rinsed twice with cyclohexane, and a solution of 0.166 g of concentrated hydrochloric acid in 1 ml of water are added to the reaction mixture. The reaction mixture is heated at 60-62 degrees for 1.5 hours after the peroxide has been added. After work up and purification according to the procedure of Example 54, the yield of the title compound is 5.53 g (75% yield), GC assay 96%.
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