2010 年 68 巻 2 号 p. 160-168
The chemistry of CO2 has received much attention from the viewpoint of carbon resources and environmental problems, and the fixation of CO2 represents an attractive area in both organic and green chemistries. In this account, we describe a new synthetic methodology about “CO2-recycling transformation reactions”, in which the reaction would proceed via decarboxylation of the substrate followed by re-fixation of the resulting CO2. Phenoxy-substituted cyclic carbonates were produced when the palladium-catalyzed reactions of propargylic carbonates having a hydroxyl group with phenols were carried out. Applications to diastereo- and enantioselective reactions succeeded with high selectivities. Allylic and 1,3-dienylic carbonates were converted to the vinyl-substituted cyclic carbonates in the presence of palladium catalyst. Oxazolidinones were synthesized by the reaction of allylic carbonates having a amino group. DBU-promoted CO2-recycling reaction of propargylic carbonates also proceeded to afford the 5-vinylideneoxazolidin-2-ones.