Categories: C-Cl Bond Formation >
Synthesis of 1,2-dichloroalkanes
A stereospecific triphenylphosphine oxide-catalyzed 1,2-dichlorination reaction of epoxides is effective for a range of terminal and internal epoxides. In contrast to the classical Appel-type dichlorination of epoxides, oxalyl chloride is used as a stoichiometric reagent to generate the chlorophosphonium salt responsible for dichlorination from catalytic triphenylphosphine oxide.
R. M. Denton, X. Tang, A. Przeslak, Org. Lett., 2010, 12, 4678-4681.
A mild and efficient protocol enables the preparation of 1,2-dichloroalkane derivatives from olefins in the presence of NH4Cl and Oxone at room temperature. Various terminal, internal, and cyclic alkenes reacted smoothly to give the corresponding dichlorinated products in good to excellent yields. Internal olefins dichlorinated with moderate to excellent diastereoselectivity.
P. Swamy, M. M. Reddy, M. A. Kumar, M. Naresh, N. Narender, Synthesis, 2014, 46, 251-257.