Experiment 3 Resolution Of Phenylethylamine

Experiment # 3 – Resolution Of
( )- -Phenylethylamine

Name: Krishna Binu
Class: Chem 2020
Due Date: October 23, 2015

Table 1 Shows the experimental results.

Name Result
Mass of Amine (g) 3.32
Mass of Salt (g) 1.26
Observed Rotation of Isolated Amine (Degrees) -36.33

1) Draw the chemical structures of the two diastereomeric salts produced in Part A using a proper perspective (line-angle) representation. Please note: (+)-tartaric acid has the (R,R) configuration. Pay special attention to the geometry of the stereocentres in each ion. Clearly label each stereocentre as (R) or (S).

Drawing in the Hard copy

2) Calculate the yields of collected salt and isolated amine to the nearest %.

Percent yield of isolated Amine

Observed rotation = -36.33
(-36.33)/(0.94g/mlx1) = -38.64
Percent yield = (-38.64/40.4) x100 = 95.67%

4) What would happen if you did not add the 2 M NaOH solution to the amine tartrate salt prior to extracting the amine with dichloromethane?
If the 2M NAOH were not added to the amine tartrate salt during the extraction method then the separation of amine wouldn’t have been possible. When the NAOH is added to the mixture, it covert the salt back to amine.

5) If you used (-)-tartaric acid in your experiment, what salt would you obtain in the precipitate? Which isomer of α-phenylethylamine would you get from this?

The salts will have a (-)(-) and (+)(-) combination
Salt that would obtain will be (+) amine (-) Tartrate