Barbital synth.

[Snooby]

I have all precursors. look as easy synth.

But some question how can i see if the diethylmalonylchloride is separated from phosphorusoxychloride?

1 mol of diethyl malonic acid is warmed gently with 2 moles of phosphorus pentachloride oxychloride, and purified by distillation collecting fraction passing at 197° C. 1 mole of diethylmalonyl chloride is mixed with 1.1 mole of finely powdered dry urea and heated for 20 hours at 90-100° C. Hydrochloric acid is evolved, and finally there remains a solid mass which, on crystallization from hot water, affords pure barbital.

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