video tutorial Diethylmalonate synthesis from chloroacetic acid

Diethyl malonate synthesis from chloroacetic acid — summary

• Goal: prepare diethyl malonate via malonate esterification from chloroacetic acid.
• Step 1: generate a strong alkali cyanide solution from a cyanide melt (from sodium metal and potassium peroxide) and remove solid iron.
• Step 2: convert chloroacetic acid to sodium chloroacetate by reacting with sodium hydroxide in cold water/ice, then adjust to slightly alkaline.
• Step 3: hydrolyze cyanoacetate with sodium hydroxide while heating, releasing ammonia, to form sodium malonate; acidify to precipitate malonate; remove iron-induced coloration.
• Step 4: dry and extract malonate with hot ethanol, re-extract to maximize dissolution.
• Step 5: esterify malonic acid with excess absolute ethanol in the presence of a catalytic amount of sulfuric acid, reflux for about 5 hours, then distill off ethanol.
• Step 6: separate organic (diethyl malonate) from aqueous layer, wash with bicarbonate to remove residual acid, dry with calcium chloride.
• Step 7: yield about 14 g of crude diethyl malonate from roughly half of the chloroacetic acid batch (≈17%), notes that purification of malonic acid before esterification could improve yields; product has fruity aroma.
• Overall: process is lengthy and arduous; future work to improve yield and efficiency.