One-pot conversions of olefins to cyclic carbonates and secondary allylic and homoallylic amines to cyclic carbamates.
Davies SG., Fletcher AM., Kurosawa W., Lee JA., Poce G., Roberts PM., Thomson JE., Williamson DM.
Sequential treatment of a 1,2-disubstituted olefin with m-CPBA, Br3CCO2H, and DBU results in the one-pot, stereospecific conversion of the olefin to the corresponding disubstituted cyclic carbonate (1,3-dioxolan-2-one). The reaction proceeds via an initial epoxidation followed by S(N)2-type epoxide ring opening by Br3CCO2H and subsequent base-promoted carbonate formation upon elimination of bromoform. When a solution of a secondary allylic or homoallylic amine and Br3CCO2H is sequentially treated with m-CPBA then DBU, the product of the reaction is a cyclic carbamate (1,3-oxazolidin-2-one or 1,3-oxazinan-2-one).