The Pd-catalyzed three-component coupling of readily available aryl iodides, internal alkynes, and arylboronic acids provides a convenient, one-step route to tetrasubstituted olefins in good to excellent yields in scCO(2) using CsOAc as base. The final optimized reaction conditions for the three-component coupling in scCO(2) was determined to be aryl iodides (0.5 mmol), internal alkynes (0.25 mmol), and arylboronic acids (0.5 mmol) in the presence of PdCl2 (2 mol%) and CsOAc (0.75 mmol) in scCO(2) (P-CO2 = 7.5 MPa) at 100 degrees C for 24 h. The presence of scCO(2) generally substantially improved this Pd-catalyzed system and increased the yields of the desired tetra substituted olefins. The reaction involves full cis-addition of internal alkynes and this system in scCO(2) is an effective and environmental friendly alternative to the previous methods involving organic solvent. (C) 2009 Elsevier B.V. All rights reserved.