A silver/DBU catalyst system was developed for the effective synthesis of cyclic carbonate and oxazolidinone from the reaction of CO 2 with propargylic alcohols and propargylic amines, respectively, in high yields under mild conditions. It was found that the [3,3]-sigmatropic MeyerSchuster-type rearrangement of the propargylic alcohol was mediated by CO 2 in DMF to afford the corresponding ¡,¢-unsaturated carbonyl compounds in high yields. The silver salt combined with the chiral Schiff base ligand could be applied to enantioselective chemical CO 2 incorporation into various bispropargylic alcohols to produce the corresponding cyclic carbonate in high yields with high enantioselectivity. The absolute configuration was determined by VCD spectroscopy as well as by X-ray analysis. These products were found to be active for the aminolysis reaction to afford the corresponding carbamate derivatives in high yields without any loss of optical purity.An enormous amount of energy has been generated by the oxidation of hydrocarbons in order to make our life comfortable and convenient while generating an enormous amount of CO 2 worldwide.1 Because the most oxidized form of the carbon derivatives is much less reactive, its application to organic synthesis has been considered to be one of the most challenging research topics. As well as the chemical fixation of CO 2 , much effort has been made to utilize CO 2 as an attractive C1 feedstock for organic synthesis due to its ubiquitous, abundant, and nontoxic properties, however due to its lower reactivity, harsh reaction conditions are required to activate and incorporate CO 2 into organic compounds.2 It is necessary to develop a mild reaction system including catalysts to efficiently capture CO 2 into a wide variety of substrates, especially fine-chemicals. Various synthetic reactions of CO 2 have been reported. Typically enol derivatives, 3 Grignard reagents, 4 and alkyllithium compounds 5 readily react with CO 2 to afford the corresponding carboxylic acids, though a stoichiometric amount of a strong nucleophile is employed. Transition-metals, such as nickel, 6 rhodium, 7 palladium, 8 copper, 2e,9 and gold, 2e can catalyze the reaction of CO 2 to produce the corresponding carboxylic acid and lactone derivatives. However, it is required to prepare in advance reactants containing a boron, halogen moiety, etc., and the scope and applicability are limited.It was recently found that a catalytic amount of a silver salt as a ³-Lewis acid to activate an alkyne combined with the use of DBU is an efficient catalyst system for the reaction of CO 2 with propargylic derivatives. We now report that a silver salt/DBU combination catalyzes the reaction of CO 2 with propargylic alcohols 10a and propargylic amines 10b to produce the corresponding cyclic carbonates and oxazolidinones in good to excellent yields, respectively. We also describe that a MeyerSchuster-type rearrangement is mediated by CO 2 in the presence of a catalytic amount of silver methanesulfonate and a base to afford the corre...