The Ultrasmall Palladium Nanoparticles Catalyzed Telomerization of CO2with 1,3-Butadiene at Room Temperature: Selective Synthesis ofδ-Lactone

An efficient method for the selective synthesis of delta-lactone from CO(2)and 1,3-butadiene was developed by using ultrasmall palladium nanoparticles as a catalyst for the first time. Palladium nanoparticles (1.90 +/- 0.39 nm) were generated in situ in the presence of Pd(acac)(2), tetrabutylammonium acetate (TBAAc), and PPh(3)as the precatalyst, stabilizer, and reductant, respectively. Maximum yield (86 % with 96 % selectivity) with satisfactory conversion (89 %) and turnover number (1271) was achieved under mild conditions.