To a beaker add 4 g of chloral hydrate, 4.2 mL of chlorobenzene and slowly 36 mL of cold sulfuric acid, stir vigorously. Stir for an hour and then cap the beaker and let the mixture stand for 24 h. After 24 h stir for 10 minutes and let the mixture stand for 5 days while the beaker is capped. Then pour the mixture into 200 mL of ice water, stir, filter and wash with 50 mL of 5 % sodium carbonate solution. Recrystallize in IPA 4:1 water solution.
The mixture darkens
Pouring the mixture into cold water and then filtering
The recrystallized product