Specific solvent issues with iodination
Many iodinations have traditionally been carried out in chlorinated solvents CCl4, CHCl3, C2H4Cl2 and CH2Cl2. These should be avoided if possible. If a chlorinated solvent is needed, CH2Cl2 should be employed.
A number of I+ reagents can react with certain solvent classes, and hypervalent iodine compounds can be explosive.
Some iodination reactions have been reported in water as the solvent. Caution should be exercised in water containing ammonia since the explosive NI3 could potentially be formed.