反应详情

A chloroform solution of maltol (1) is mixed with a 1M solution of zinc chloride in ethanol to provide a 2:1 molar ratio of maltol: zinc in the mixture. After 5 minutes at 20° C., a 10 molar excess of solid sodium carbonate is added and the mixture is stirred for 10 minutes. The mixture is then filtered and the solvent evaporated to give the neutral complex containing maltol and Zn++ in a 2:1 proportion. Recrystallisation of the 2:1 complex from ethanol gives a white crystalline solid in essentially quantitative yield, m.p. 203°-204° C. (with decomposition); νmax (nujol) 1632, 1603 cm-1 ; δ(d6DMSO) 7.96 (d, 1H), 6.40 (d, 1H), 2.20 (s, 3H).

1. customto provide a 2
2. filtrationThe mixture is then filtered
3. customthe solvent evaporated
4. customto give the neutral complex
5. customRecrystallisation of the 2:1 complex from ethanol
6. customgives a white crystalline solid in essentially quantitative yield, m.p. 203°-204° C. (with decomposition)