One-Pot Synthesis of Cyclic Carbonates from Aldehydes, Sulfur Ylide, and CO2

Treatment of aldehydes with sulfur ylide (CH₂=SOMe₂ or CH₂=SMe₂), in the presence of CO₂ (1 atm) bubbled sequentially under mild conditions, produces cyclic carbonates in preparative yields. Sodium iodide formed in situ promotes the reaction between epoxide as intermediate and CO₂ at ambient conditions, thus constituting a powerful metal-free synthesis of organic cyclic carbonates directly from aldehydes.