[mcdull1016]

1. Why do we use 3 mol of diethylamine with 1 mol of alpha-chloro-2,6-dimethylacetanile in the reaction?
ans i think: is it becoz to make sure the nucleophile is strong enough?

2. Why do we need to extract twice with pentane when isolating and purifying the product lidocaine?

Thanks in advance!! XD

[AWK]

You need at least 2 moles of diethylamine
alpha-chloro-2,6-dimethylacetanile 2C4H11N = Lidocaine + C4H12NCl
Extraction is an equilibrium process, hence you need repeat the extraction a few times to increase practical yield. Lidocaine itsel is soluble in organic solvents, where us its hydrochloride is soluble in water together with diethylammonium chloride.