Benzene-1,2-dicarb-oxy-lic acid-pyridinium-2-olate (1/1)

Chua-Hua Yu1

  • 1Orderd Matter Science Research Center, Southeast University, Nanjing 211189, People's Republic of China.

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For disubstituted benzene derivatives, with two groups attached to the benzene ring, three constitutional isomers are possible. For example, consider dimethyl benzene, often called xylene, where the second methyl group can be substituted at the second, third, or fourth carbon. The relative position of the substituents is represented by prefixes ortho, meta, or...
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