Question

My suggestion is to perform an extraction... but I want to make sure if im correct.

A co-worker is conducing a distillation on a mixture that includes a new precursor that will be used in the drug pipeline to differentiate alternate final products. The precursor melts at -20°C and boils at 163°C. While performing a simple distillation, the mixture in the boiling flask turns brown as the receiving flask collects distillate at 80.2°C. No distillate was collected near the target temperature.

At the team meeting your co-workers asks for advice. What do you suggest knowing only what is stated here?

Select one:

a. Perform another simple distillation

b. Perform a TLC

c. Perform a recrystallization

d. Perform a vacuum distillation

e. Perform a fractional distillation

f. Perform an extraction

Answer 1

(a) Simple distillation failed, already, compomund is decomposing at around 80^oC, so repeating it will not be nelpful'

(b) TLC is an anlyticall tool, it is used to find out the composition of the mixture or purity of the sample, quqlitatively - will not be able to separate the compound.

(c) The melting point is - 20^oC, it is liquid compound, will not be easy to do the recrystalliation.

(d) Distillation under vaccum may be a good idea because the compound can be distill out at much lower temperature preventing the decomposition and the vacuum can adjusted based on the impurity profile of the crude. Is the right answer.

(e) Fractional distillation is done to separate compounds with boiling points close to each other - will not be helpful here.

(f) Extraction is a separation method which probably was done sfter the reaction - it can not purify the material.