Original scientific paper

Mechanism of Levulinic Acid Formation in Acid Catalysed Hydrolysis of 2-Hydroxymethylfurane and 5-Hydroxymethylfurane- 2-carhaldehyde

Jaroslav Horvat ; »Ruđer Bošković« Institute, Department of Organic Chemistry and Biochemistry, 41001 Zagreb, P. O. B. 1016, Yugoslavia
Branimir Klaić ; »Ruđer Bošković« Institute, Department of Organic Chemistry and Biochemistry, 41001 Zagreb, P. O. B. 1016, Yugoslavia
Biserka Metelko ; »Ruđer Bošković« Institute, Department of Organic Chemistry and Biochemistry, 41001 Zagreb, P. O. B. 1016, Yugoslavia
Vitomir Šunjić ; »Ruđer Bošković« Institute, Department of Organic Chemistry and Biochemistry, 41001 Zagreb, P. O. B. 1016, Yugoslavia

Abstract

Mechanism of levulinic acid (2) formation in acid catalysed hydrolysis of 2-hydroxymethyl£urane (3) and 5-hydroxymethylfuran- 2-carbaldehyde (1) is studied by 13C-NMR spectroscopy. Hydroxymethyl-derivative of dihydrofurane 5, its anhydro-derivative
6, and an unsaturated keto-aldehyde (8) are determined as intermediates in the transformation of 3 into 2 (Scheme 3). The conversion of 1 into 2 requires more drastic conditions, and
the only two structures determined unambigously are 15 and 16;
the former intermediate led to polymerized material via A-5,
analogous to polymerization of 4 via 13 and 14 (Scheme 4), while
the latter decarbonylates and rearranges to afford levulinic acid
(Scheme 5). Intramolecular oxygen transfer via cyclic intermediates
(Scheme 6), embracing concerted C(l)-O and C(5)-X (X = H or eHO) bond breaking, cannot be proved.

Keywords

Hrčak ID:

177372

URI

https://hrcak.srce.hr/177372

Publication date:

20.6.1986.

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