Ethyl maltol can be commercially produced by chemical synthesis, generally with the manufacturing process of Grignard reagent preparation, grignard reaction, hydrolysis, chlorination and rearrangement reaction.

Firstly to obtain Grignard reagent (CH3CH2MgBr) by the reaction of magnesium with CH3CH2Br in the presence of anhydrous ether or tetrahydrofuran solvent.

Then react the Grignard reagent with furfural, and then hydrolyzed to obtain furfuryl alcohol intermediate. Chlorinate the furfuryl alcohol intermediate at low temperature, and then heated to hydrolyze and rearrange to obtain crude maltol in acidic medium, and finally purified by sublimation and recrystallized in ethanol. (1)

Here is the general flow chart:

ethyl maltol manufacturing flow chart
R=CH3CH2-

Properties
Other names    2-ethyl-3-hydroxy-4-pyrone
CAS number    4940-11-8
Chemical formula    C7H8O3
Molecular weight    140.14
Melting point    89-93 ℃
FEMA number     3487
Solubility
Sparingly soluble in water; soluble in ethanol and in propylene glycol (can be diluted to 10%).