Synthesis of Monomeric Cyclic Carbonates

6 Reaction Mechanisms in the Direct Carboxylation of Alcohols, Polyols... 

In the case of Bf2 promoted carboxylation [171], Br is supposed to attack the oxygen of the epoxide whereas Br stabilizes the carbocation. This is a particular case, as it is known that bromine in the presence of bases affords Br and BrOs or BrO , according to the conditions. 

SC-CO2 is often used as solvent and reagent and is considered to be an economically viable and ecologically benign reaction medium. It has several advantages such as no flammability, lack of toxicity, absence of a gas-liquid phase boundary, and possible simplifications in workup. The advantages of using SC-CO2 alone [172] or in combination with IL [173, 174] have been described. Amides play a 

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