Abstract
Meldrum's acid (2) is acylated by diketen affording the acylMeldrum's acid3. In aqueous bicarbonate its 3-oxogroup is selectively reduced by sodium tetrahydroborate giving the alcohol4, which readily undergoes cyclization in refluxing dioxane leading to the title pyrone7. Under identical conditions3 produces the pyrone6 with the pyrone carboxylic acid5 as intermediate.
This is a preview of subscription content, log in via an institution to check access.
Literatur
Tschesche R., Hoppe H.-J., Snatzke G., Wulff G., Fehlhaber H.-W., Chem. Ber.104, 1420 (1971).
Nedjar B., Hamdi M., Périé J., Hérault V., J. Heterocycl. Chem.15, 1153 (1978) und dort zitierte Lit.
Bacardit R.,Moreno-Mañas M., Tetrahedron Lett.1980, 551.
6 ist aus dem Diketendimerisierungsprodukt Dehydracetsäure darstellbar (siehe Lit.7).
Izawa T.,Mukaiyama T., Tetrahedron Lett.1975, 161.
Oikawa Y., Sugano K., Yonemitsu O., J. Org. Chem.43, 2087 (1978);Houghton R. P., Lapham D. J., Synthesis1982, 451.
Suzuki E.,Sekizaki H.,Inoue S., Synthesis1975, 652.
Collie J. N., J. Chem. Soc.59, 607 (1891).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Häusler, J. Notiz zur Darstellung von 4-Hydroxy-6-methyl-5,6-dihydro-2H-pyran-2-on. Monatsh Chem 113, 1213–1216 (1982). https://doi.org/10.1007/BF00808633
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00808633