ABSTRACT
The palladium-catalyzed hydroesterification reaction was performed with polyols and olefins in a liquid/liquid biphasic system composed of unreacted polyol on the one hand and apolar reaction products/organic solvents on the other hand. The palladium-based catalyst was immobilized in the polyol phase thanks to the use of cationic triarylphosphines possessing pendent protonated amino groups in the acidic reaction medium or to the sulfonated phosphine TPPTS (trisodium triphenylphosphine-3,3',3''-trisulfonate). Owing to the insolubility of the products in the catalytic phase, this approach allowed the synthesis of monoesters of polyols with high selectivities as well as the easy separation of the catalyst through simple decantation.
Subject(s)
Palladium/chemistry , Polymers/chemistry , Alkenes/chemistry , Catalysis , Chemistry Techniques, Synthetic , Esterification , EstersABSTRACT
The hydroesterification of alpha olefins has been used to synthesize diesters from bio-based secondary diols: isosorbide, isomannide, and isoidide. The reaction was promoted by 0.2% palladium catalyst generated inâ situ from palladium acetate/triphenylphosphine/para-toluene sulfonic acid. Optimized reaction conditions allowed the selective synthesis of the diesters with high yields and the reaction conditions could be scaled up to the synthesis of hundred grams of diesters from isosorbide and 1-octene with solvent-free conditions.
