1,3,5-Triiodobenzene is used in the synthesis of conjugated microporous polymers through cationic cyclization polymerization. It also can be used in optical materials.
1,3,5-Triiodobenzene was synthesized by reacting 2,4,6-triiodoaniline with NaNO2 in the presence of copper(I) oxide.
Experimental procedure: Finely ground NaNO2 (1.95 g,
0.028 mol) was slowly added with stirring to sulfuric acid
(3.5 mL). Then a solution of 2,4,6-triiodoaniline(2.90 g,
6.16 mmol) in glacial AcOH (130 mL) was added dropwise with
stirring and cooling at such a rate that the temperature of the
reaction mixture was kept below 20 °C. Following addition of
the amine, the reaction mixture was stirred at ≈20 °C for about
30 min. The resulting solution of the diazonium salt was added
dropwise to a suspension of copper(I) oxide (2.52 g) in dry ethanol (70 mL) with vigorous stirring over 15 min. The reaction
mixture was brought to boiling and stirred for 30 min until
elimination of nitrogen ceased. Then the mixture was cooled,
kept for one day, poured into ice water (300 mL), and extracted
with benzene (3×50 mL). The benzene extracts were dried with
anhydrous Na2SO4 and the solvent was distilled off in vacuo.
The residue was repeatedly recrystallized from benzene. The
yield was 2.01 g (84%), m.p. 182 °C (cf. lit. data11: m.p. 183 °C).
1H NMR (CDCl3), δ: 8.02 (s, 3 H, CH). 13C NMR (CDCl3),
δ: 79; 128.
