Question

Dissolve 12.5 g (0.103 mole) recovered amine, [α]D27: +24.50, in 88 ml of 95% ethanol. (This solution contains 0.062 mole excess +)-amine, based on [a]D2: +40.7° for the pure (+)-amine, and 0.041 mole racemic amine Heat the solution to boiling and add to it a solution of concentrated sulfuric acid (3.2 g of 98% 112804; 0.032 mole H,SO.) in 180 ml of 95% ethanol. After allowing the mixture to cool slowly to room tem perature, collect the crystalline (+)-amine sulfate by suction filtration and wash it thoroughly with ethanol Yield: 7.8 g (74%) Isolate the free (±)-amine as described above (treat- ment with sodium hydroxide exuractionand distilla tion) using 40 ml of water and 5 mt r30% sodium hydroxide for each 10 g of the sulfate salt. Yield: 4.4 g (59%); bp : 184-180°; [a]D27: +38.3° (lit. : [a]D22: +40.67 (5)

After I made extraction I put dry agent ( sodium magniusm) and the lab time is up and I left it for two days insteaf of 10 mins and all my product is gone

Can you pease think if reasons why nothing left ?

Answer 1

May be the solvent which has been used to collect the amine is evaporated slowly in two days. You may recover it by using the same solvent you have used before (provided the amine has not been decomposed)

( This is common thing which happens in synthesis lab. If the product has been left in the solvent kept with drying agent overnight, the solvent evaporates leaving behind only the drying agent and the compund. If the compound is stable enough it can be recovered using the same solvent)