镍卟啉临氮和临氢反应行为的研究

通过高压连续微型反应装置,对镍-2,3,7,8,12,13,17,18-八乙基卟啉(Ni-OEP)在氮气和氢气中的反应行为进行了研究,实验结果表明,镍卟啉在氮气中的稳定性非常高,只有在高温(500℃左右)下才发生分解;而在氢气中,镍卟啉的生经低,即使不存在催化剂,反应条件较为温和(温度不超过400℃,压力小于10MPa),也有相当一部分镍卟啉发生分发,脱除所配合物的金属;镍卟啉的临氢脱金属反应过程中分两步,第一步是卟啉分中一个吡咯环上的外环双键加氢生成镍卟酚,第二步镍卟酚分解,金属脱除.

REACTION CHARACTERISTICS OF NICKEL PORPHYRIN IN PRESENCE OF N_2 AND H_2

The reaction characteristics of nickel 2,3,7,8,12,13,17,18-octaethylporphyrin (Ni-OEP) in the presence of N2 and H2 have been investigated by using a high-pressure flow microreactor. In the presence of N2, Ni-OEP is very stable, and there is no reaction below 420?℃ and it only decomposes at high temperature (about 500?℃). But in the presence of H2, even in the absence of a catalyst and under mild reaction conditions, Ni-OEP can decompose and nickel is removed. The demetalation of Ni-OEP in the presence of H2 consists of two steps. The first step is hydrogenation of nickel porphyrin to nickel chlorin, and the second step is decomposition of nickel chlorin and the removal of nickel.