Pd-Catalyzed Cyclocarbonylation of Allylic Alcohol under Benign Conditions with Ionic Liquid as Stabilizer
Journal article, 2020

Homogeneous palladium-catalyzed (Pd-catalyzed) cyclocarbonylation of unsaturated allylic alcohols and alkynols in the presence of hydrogen forms lactone products with important applications in the food, perfume, and polymer industry. In this work, the cyclocarbonylation of 2-methyl-3-buten-2-ol was studied for the first time using a very active Pd-DPEphos (bis[(2-diphenylphosphino)phenyl]ether) catalyst in the presence of the ionic liquid (IL) [BMIM]Cl (1-butyl-3-methylimidazolium chloride) in dichloromethane to selectively produce 4,4-dimethyl--butyrolactone. The effect of different parameters such as temperature, gas partial pressures, time of reaction, substrate and ligand concentrations were investigated and found to provide optimal conditions for lactonization (95 °C, 28 bar (CO/H2/N2: 20/5/3)), 18 h, 0.1 M substrate, and 16 mol% DPEphos), which were significantly milder than previously reported systems for cyclocarbonylation. Importantly, the study further showed that presence of the IL in the reaction mixture provided stabilization of the catalyst system and prevented formation of Pd-black, which allowed reuse of the catalytic system in consecutive reactions after intermediate extraction of the lactone product.

allylic alcohol

Pd-diphosphine catalyst

cyclocarbonylation

ionic liquid

lactone production

catalyst stabilization and recycling

Author

Nasrin Nemati

Shiraz University

Technical University of Denmark (DTU)

R. Eslamloueyan

Shiraz University

A. Modvig

Technical University of Denmark (DTU)

A. Riisager

Technical University of Denmark (DTU)

Materials

1996-1944 (ISSN)

Vol. 13 9 2093

Subject Categories

Manufacturing, Surface and Joining Technology

Metallurgy and Metallic Materials

Condensed Matter Physics

DOI

10.3390/ma13092093

More information

Latest update

2/18/2021