Pd-Catalyzed Cyclocarbonylation of Allylic Alcohol under Benign Conditions with Ionic Liquid as Stabilizer
Artikel i vetenskaplig tidskrift, 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

Författare

Nasrin Nemati

Shiraz University

Danmarks Tekniske Universitet (DTU)

R. Eslamloueyan

Shiraz University

A. Modvig

Danmarks Tekniske Universitet (DTU)

A. Riisager

Danmarks Tekniske Universitet (DTU)

Materials

19961944 (eISSN)

Vol. 13 9 2093

Ämneskategorier

Bearbetnings-, yt- och fogningsteknik

Metallurgi och metalliska material

Den kondenserade materiens fysik

DOI

10.3390/ma13092093

Mer information

Senast uppdaterat

2021-02-18