Catalytic synthesis of bioactive 2H-chromene alcohols from (-)-isopulegol and acetone on sulfonated clays

• Type: Article in International Scientific Journal
• Date: 2020

Authors

Laluc, M (Author) Other; Maki Arvela, P (Author) Other; Peixoto, AF (Author) FCUP; Li Zhulanov, N (Author) Other; Sandberg, T (Author) Other; Salakhutdinov, NF (Author) Other; Volcho, K (Author) Other; Cristina Freire (Author) FCUP; Sidorenko, AY (Author) Other; Murzin, DY (Author) Other

Journal

Title: Reaction Kinetics, Mechanisms and Catalysis

Vol. 129

Pages: 627-644

ISSN: 1878-5190

Publisher: Springer Nature

Indexing

ISI Web of Knowledge - 6 Citations

Scopus - 8 Citations

Other information

Authenticus ID: P-00R-S34

DOI: 10.1007/s11144-020-01740-9

Abstract (EN): Condensation of (-)-isopulegol with acetone was investigated at 25-40 degrees C over clay based materials (K10, cloisite Na+ and halloysite nanotubes) modified with sulfonic acid groups by one-pot sulfonation with chlorosulfonic acid or via organosilylation with 2-(4-chlrosulfonylphenyl)-ethyltrimethoxysilane. The target product was the R diastereomer of dimethyl-substituted octahydro-2H-chromen-4-ol with exhibits antiviral activity. The catalysts were characterized by a range of physico-chemical methods. The effect of the initial isopulegol concentrations on the yield of ketone-derived chromenols and the R/S isomers ratio was studied for the first time. The best catalyst was a highly acidic, large pore K10-clay modified by sulfonic acid. Varying the initial concentration of the reagents allows to find a balance between dehydration by-products and a side etherification reaction. A high yield (73%) of the desired chromenols was reached using 0.52 mol/l initial (-)-isopulegol concentration after 240 min at 87% substrate conversion and reaction temperature 25 degrees C. The yield exceeded that of other previously reported in the open literature catalysts.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 18