Para-nitrofluorobenzene

Display electrostatic potential maps for phenyl fluoride, para-nitrofluorobenzene and 2,4,6-trinitrofluorobenzene. Which should be the most susceptible toward nucleophiUc attack Which should be the least susceptible Explain. 

Is para-nitrofluorobenzene more or less susceptible to attack by methoxide than fluorobenzene Calculate the energetics of the reaction. (Energies for phenyl fluoride and para-nitrofluorobenzene methoxide anion adducts are available.)... 

Electrostatic potential map for para-nitrofluorobenzene shows positively-charged regions (in blue) as likely sites for nucleophilic attack. 

Two of three nitrofluorobenzene isomers react with methoxide, but the third is unreactive. Obtain energies of methoxide anion (at left), ortho, meta and para-nitrofluorobenzene, and the corresponding ortho, meta and para-methoxide anion adducts (so-called Meisenheimer complexes). Calculate the energy of methoxide addition to each of the three substrates. Which substrate is probably unreactive What is the apparent directing effect of a nitro group Does a nitro group have the same effect on nucleophilic aromatic substitution that it has on electrophilic aromatic substitution (see Chapter 13, Problem 4) Examine the structures and electrostatic potential maps of the Meisenheimer complexes. Use resonance arguments to rationalize what you observe. 

Display electrostatic potential maps for phenyl fluoride, para-nitrofluorobenzene and 2,4,6-trinitrofluorobenzene. 

Fluoronitrobenzenes or Nitrofluorobenzenes, (ortho-, meta- and para-), F.C6H4(N02) mw 141.11, N 9.94%. Prepd by variety of nitration methods from fluorobenzene. Its para-compd is described in Ref 1, as pale yel... 

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