An organic compound having a nitroxide free radial of the formula (2) is prepared by reacting a cyclic secondary amine having a steric hindrance of the formula (1) with a peroxide in the presence of at least 1 part by weight of an organic compound having a cyano group per 1 part by weight of the cyclic secondary amine having the steric hindrance. In the formulae (1) and (2), T is a methylene group, an ethylene group, an oxygen atom or a methyleneoxy group; R is an alkyl group, an aralkyl group, an aryl group, a cycloalkyl group, an alkoxy group, an acyl group an acyloxy group, an amino group, a hydroxyl group or a heterocyclic group; R1, R2, R3 and R4 are the same or different and each an alkyl group or an aryl group, or R1 and R2 and/or R3 and R4 together form a tetramethylene group or a pentamethylene group; and n is an integer of 0 to 6.
一种具有式(2)的游离硝基径向的有机化合物的制备方法是将具有式(1)的立体阻碍的环状仲胺与过氧化物反应,反应时每 1 重量份具有立体阻碍的环状仲胺至少有 1 重量份具有
氰基的有机化合物存在。在式 (1) 和 (2) 中,T 是亚甲基、亚乙基、氧原子或亚甲基氧基;R 是烷基、芳基、芳烷基、环烷基、烷氧基、酰基、酰氧基、
氨基、羟基或杂环基;R1、R2、R3 和 R4 相同或不同,且各自为烷基或芳基,或 R1 和 R2 和/或 R3 和 R4 共同形成四亚甲基或五亚甲基;且 n 为 0 至 6 的整数。