A Highly Regioselective and Solvent-Free Sn(II)-Catalyzed Glycerol Ketals Synthesis at Room Temperature

• Published in: Catalysis letters Vol. 145; no. 3; pp. 769 - 776
• Main Authors: da Silva, Márcio José, de Oliveira Guimaraes, Matheus, Julio, Armanda Aparecida
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01-03-2015; Springer Nature B.V
• Subjects: Carbon; Catalysis; Catalysts; Chain branching; Chains; Chemical reactions; Chemical synthesis; Chemistry; Chemistry and Materials Science; Derivatives; Glycerol; Industrial Chemistry/Chemical Engineering; Isomers; Ketones; Organometallic Chemistry; Pentanone; Physical Chemistry; Regioselectivity; Room temperature; Solvents; Stoichiometry; Tin; Tin chloride; Glycerol; Bioadditives; Ketalization; Tin salt catalysts
• ISSN: 1011-372X; 1572-879X
• DOI: 10.1007/s10562-015-1477-8

Herein, an efficient and environmentally benign tin-based process who is a simple and available commercially catalyst, was used in the glycerol ketalization with different ketones at room temperature and solvent-free reactions. Although being a molecule highly functionalized, glycerol was selectively converted to ketal in all the SnCl
2
-catalyzed reactions. A high regioselectivity (ca. 78–99 % for 1,3-dioxolane derivatives) was achieved for ketones with straight or cyclic chain having up to six carbon atoms. Conversely, glycerol ketalization with branched carbon chain ketones containing six carbon atoms (i.e. 4-methyl-2-pentanone) resulted in the equimolar formation of two isomers products (i.e.
cis
and
trans
-1,3-dioxolane isomers glycerol derivatives). The main reaction parameters such as the ketone nature, reactants stoichiometry and catalyst concentration were assessed. The SnCl
2
catalyst operate at mild and solvent-free reaction conditions and was successively recovered and reused without activity loss.
Graphical abstract
Tin-catalyzed glycerol ketal synthesis