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富勒烯的化学活性越来越引起人们的广泛关注,C_(60)O的氧化是实验上和理论上研究得较早和较深入的课题.C_(60)O可以通过各种方法得到:其中臭氧氧化是常用和有效的方法之一.理论上有用从头算(HF/3-21G)MNDO,INDO及紧束缚分子力学等法对C_(60)O进行系统研究.理论计算结果表明C_(60)O有两种异构体:一是氧加成在[6-6]键上,形成环氧结构,具有C_2v对称性[记为C_(60)O(C_2v)].另一是氧加在[6-5]键上,键断裂形成开环的轮烯结构,有C_s对称性[记为C_(60)O(C_s)].~(13)C NMR和X射线晶体结构分析表明C_(60)O主要异构体为C_(60)O(C_2v).对异构体C_(60)O(C_s),人们只在理论上讨论,未见报道它实验上存在.本文用臭氧氧化C_(60)的苯溶液,用HPLC分析产物,室温下氧化产物只得到一个C_(60)O异构体组分峰.低温下产物得到两个C_(60)O异构体组分峰.多出的一个峰经实验与理论的研究,表明它很可能是异构体C_(60)O(C_s).
The chemical activity of fullere is attracting more and more attention, and the oxidation of C 60 O has been studied both experimentally and theoretically.C_ (60) O can be obtained by various methods: Among them ozone oxidation is one of the common and effective methods.It is theoretically possible to systematically study the C 60 O with theoretical ab initio calculations (HF / 3-21G) MNDO, INDO and tight binding molecular mechanics, etc. The theoretical calculations show that C_ ( 60) O has two isomers: one is the addition of oxygen on the [6-6] bond to form an epoxy structure with C_2v symmetry [C_ (60) O (C_2v)] and the other is oxygen Added to the [6-5] bond and the bond cleaved to form a ring-opened annulene structure with C_s symmetry [C_ (60) O (C_s)]. ~ (13) C NMR and X-ray crystal structure analysis The main isomer of C_ (60) O is C_ (60) O (C_2v) .For the isomer C_ (60) O (C_s), it is only discussed in theory and there is no report about its existence experimentally.In this paper, Oxidation of the benzene solution of C_ (60) and the analysis of the product by HPLC showed that the product of oxidation at room temperature gave only one component of C 60 O isomer. At low temperature, the product obtained two C 60 O isomers The extra peak was studied experimentally and theoretically, indicating that it is likely to be the isomer C 60 O (C _s).