Potassium Hydroxide → (1,3-Dithiol-2-ylidene)malonic acid monomethyl ester

Participants

Reaction Conditions

Reaction Steps

Dimethyl 2-(1,3-dithiol-2-ylidene)malonate (2) (116 g) was suspended in methanol (2 l), to which a solution of 33.5 g of 85% potassium hydroxide in water (250 ml) was added. The resulting mixture was heated under reflux for 8 hours. After the solvent was removed, water (2.5 l) was added and the resulting mixture was heated to 50° C. Insoluble matter was filtered off. Concentrated hydrochloric acid (50 ml) was added to the filtrate to acidify the same. The resultant precipitate was collected by filtration and after washing, was dried at 40° C. in air, whereby 2-(1,3-dithiol-2-ylidene)-3-methoxy-3-oxopropionic acid (3) (92 g, yield: 84%) was obtained.

Provenance & Evidence