Summary

This study details the crystal structure of a pyridine-benzene compound (C12H10N2O4). Molecules form a 3D network through hydrogen bonding, with specific orientations of nitro and methoxy groups.

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All meta-directing substituents are deactivating groups. These substituents withdraw electrons from the aromatic ring, making the ring less reactive toward electrophilic substitution. For example, the nitration of nitrobenzene is 100,000 times slower than that of benzene because of the deactivating effect of the nitro group. The first step in an electrophilic aromatic substitution is the addition of an electrophile to form a resonance-stabilized carbocation. The energy diagrams for the...
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