Because of their unusual electronic structures and properties, potential applications of fullerene pyrrolidine derivatives have attracted much interest in many fields, especially in materials science. In this study, eight fulleropyrrolidine derivatives were characterized by ion trap mass spectrometry (ESI IT - MS) under electrospray ionization condition. The obtained results showed that fullerene-N-methylpyrrolidine derivatives are readily ionized with the loss of one electron by negative-ion ESI IT - MS. Some fullerene-N-methyl pyrrolidine derivatives can be protonated with positive-ion ESI IT - MS or deprotonated with negative-ion ESI IT - MS when there are some groups or atoms in the molecular structure easy to catch or lose active hydrogen. The pyrrole ring of fulleropyrrolidine derivatives is easy to lose during the process of negative-ion ESI IT - MS/MS, and Cm can be observed in all the ESI IT - MS/MS spectra of fullerene pyrrolidine derivatives. Retro-cycloaddition reactions take place in the structure of the pyrrole ring to produce mono-substituted methanofullerene with the loss of CH2 =N—CH3. Useful informations about molecular weight and structure can be obtained by ESI - MS and ESI MS/MS.%通过直接进样方式,采用电喷雾电离质谱技术分析了8个合成的富勒烯-N-甲基吡咯烷衍生物,详细研究了其在电喷雾条件下的质谱行为.由结果可知,该类化合物在电喷雾电离过程中易得到电子而负离子化；当衍生物结构中有相对易质子化基团或有活泼氢时,则可获得质子化和去质子的正负离子谱图；衍生物在负离子模式下容易失去吡咯环产生富勒烯负离子,且在合适能量碰撞下易发生衍生化基团内部的逆环加成反应,通过失去1个中性小分子物质CH2=N-CH3,产生新的一取代亚甲基富勒烯衍生物.基于电喷雾电离源技术联合离子阱分析器建立的质谱分析方法,不但能提供准确的分子量信息,还能通过获得高分辨同位素谱峰和丰富的二级碎片离子峰,进一步确认化合物的分子结构,是一种先进、快速的富勒烯吡咯烷衍生物定性分析方法.
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