题目内容

常见的核磁共振氢谱图的内标试剂（d = 0）为（）

A. TMS
B. DMSO
C. THF
DME

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下列化合物中不能发生Friedel-Crafts的是（）

A. 硝基苯
B. 苯
C. 甲苯
D. 氯苯

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C. open

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