| 摘要 |
Gamma-pyrones of the formula where R is lower alkyl of 1 to 6 carbon atoms, lower alkenyl of 2 to 6 carbon atoms or benzyl are prepared from the corresponding where R' is C1-6 alkyl. Such an intermediate may be prepared from furfural via (a) the corresponding 1-(2-furyl)-1-alkanol,(b) 2-(1-hydroxy alkyl)2,5-dialkoxy, 2,5-dihydrofuran, and(c) the corresponding 2-alkyl-2H-pyran-3-(6H). The process is of particular use for preparing maltol, pyromeconic acid and ethyl maltol. Certain of the intermediate and reactions for producing the intermediates are novel. |
