1,1-Diiodoethane is an organic saturated haloalkane containing iodine with formula CH3CHI2.
Preparation
1,1-Diiodoethane can be synthesized from gem-dihaloalkanes. The starting material is 1,1-dichloroethane, and iodoethane is a source of iodine. In the presence of aluminium trichloride, 1,1-dichloroethane will converted to 1,1-diiodoethane.[3]
To be specific, mix 0.4 mol (~39.6 g) of 1,1-dichloroethane with 1.2 mol (~187 g) of ethyl iodide, and ~2.0 g of aluminium chloride. Heat for three hours using steam bath. Then, wash the mixture with H2O and NaHSO3 respectively, and dry with MgSO4. By boiling at 76-76 °C and 25 mmHg, about 67.3 g of product will be received when distilled.[4]
The alternative method, which does not require 1,1-dichloroethane, is the reaction of iodine, triethylamine and hydrazone of acetaldehyde. Using 1 mol of acetaldehyde, about 95 g, which is 34% from acetaldehyde, of 1,1-diiodoethane formed.[4]
Application
1,1-Diiodoethane is commonly used as a reactant in reaction such as SN2. The following are some examples of SN2 reaction using 1,1-diiodoethane as a reactant.[5]
Moreover, is can also be used as a reactant in enolate substitution reaction as the following examples.[5]
^"1,1-Diiodoethane - Compound Summary". PubChem Compound Database. USA: National Center for Biotechnology Information. Identification. Retrieved 7 June 2017.
^ abBenneche, T.; Challenger, S.; Chemla, F.; Cordier, C.; Demchenko, A. V.; De Meo, C.; Diaper, C. M.; Fascione, M. A.; Ferreira, F.; Gunn, S. J.; Kouklovsky, C.; Kryezka, B.; Leach, S.; Leroy, B.; Lewkowaki, J.; Ley, S. V.; Merino, P.; Milroy, L.-G.; Myers, R. M.; Nelson, A.; Oshima, K.; Rowlands, G. J.; Roy, B.; Stalford, S. A.; Turnbull, W. B.; Angerer, S. von; Warriner, S. L.; White, J. W.; Yorimitsu, H.; Zawisza, A. (2007). Science of Synthesis: Houben-Weyl Methods of Molecular Transformations. Vol. 29. Thieme New York. p. 106. ISBN978-1-58890-461-4. Retrieved 8 June 2017.