Question

In part A of the synthesis of Lidocaine you will have to perform multiple extractions. Answer the following questions with the correct match. (bottom, top, aqueous layer, or ethereal layer)

40-50 ml of 8M KOH was added to damp solid and the pH of the solution was adjusted to be above 10. You cooled the aqueous solution and transferred it to the separatory funnel, added diethyl ether and have shaken the funnel several times. Which layer will be aqueous layer, top or bottom?
40-50 ml of 8M KOH was added to damp solid and the pH of the solution was adjusted to be above 10. You cooled the aqueous solution and transferred it to the separatory funnel and performed two sequential extractions with diethyl ether. In which layer, aqueous or etheral, the product 2,6-dimethylaniline will be found?
40-50 ml of 8M KOH was added to damp solid and the pH of the solution was adjusted to be above 10. You cooled the aqueous solution and transferred it to the separatory funnel and first portion of diethyl ether extracted the aqueous layer. Which layer you will place back into separatory funnel to extract it second time with diethyl ether, aqueous or etheral?
Potassium chloride and stannic hydroxide will be the inorganic products of the reaction with KOH. In which layer they will be found after two sequential extractions with diethyl ether, etheral layer or aqueous layer?

In part C of the synthesis of Lidocaine you will have to perform multiple extractions. Answer the following questions with the correct match. (bottom or top)

35 ml of toluene is transferred to the separatory funnel and 20 ml of 3M HCl is added, the separatory funnel has been shaken several times. Which layer will be aqueous layer, the top or the bottom?
35 ml of toluene is transferred to the separatory funnel and 20 ml of 3M HCl is added, the separatory funnel has been shaken several times. Which layer will contain the lidocaine product, the top or the bottom?
Two acidic aqueous extracts were combined and 25 nl of 8M KOH solution has been added. This solution has been transferred to the separatory funnel and 15 ml of diethyl ether has been added. The separatory funnel has been shaken several times. Which layer will be the aqueous one, the top or the bottom?
35 ml of toluene is transferred to the separatory funnel and 20 ml of 3M HCl is added, the separatory funnel has been shaken several times. To which layer the second portion of 20 ml of 3M HCl should be added, the top or the bottom?
two acidic aqueous extracts were combined and 25 nl of 8M KOH solution has been added. This solution has been transferred to the separatory funnel and 15 ml of diethyl ether has been added. The separatory funnel has been shaken several times.Which layer will contain the lidocaine product, the top or the bottom?

Answer 1

In part A of the synthesis of Lidocaine you will have to perform multiple extractions. Answer the following questions with the correct match. (bottom, top, aqueous layer, or ethereal layer)

40-50 ml of 8M KOH was added to damp solid and the pH of the solution was adjusted to be above 10. You cooled the aqueous solution and transferred it to the separatory funnel, added diethyl ether and have shaken the funnel several times. Which layer will be aqueous layer, top or bottom? >> Aqueous layer will be at bottom, heavier than diethyl ether.
40-50 ml of 8M KOH was added to damp solid and the pH of the solution was adjusted to be above 10. You cooled the aqueous solution and transferred it to the separatory funnel and performed two sequential extractions with diethyl ether. In which layer, aqueous or etheral, the product 2,6-dimethylaniline will be found? >> The product 2,6-dimethylaniline, will be in free base form at pH above 10. It will be in the ethereal layer because the free base 2,6-dimethylaniline is soluble in ether but in soluble in water.
40-50 ml of 8M KOH was added to damp solid and the pH of the solution was adjusted to be above 10. You cooled the aqueous solution and transferred it to the separatory funnel and first portion of diethyl ether extracted the aqueous layer. Which layer you will place back into separatory funnel to extract it second time with diethyl ether, aqueous or etheral? >> Aqueous layer will be extracted again, so it will be taken back to the separatory funnel.
Potassium chloride and stannic hydroxide will be the inorganic products of the reaction with KOH. In which layer they will be found after two sequential extractions with diethyl ether, etheral layer or aqueous layer? >> Inorganic salts and residues are soluble in water and will be in aqueous layer.

In part C of the synthesis of Lidocaine you will have to perform multiple extractions. Answer the following questions with the correct match. (bottom or top)

35 ml of toluene is transferred to the separatory funnel and 20 ml of 3M HCl is added, the separatory funnel has been shaken several times. Which layer will be aqueous layer, the top or the bottom? >> Bottom layer will be aqueous because toluene is lighter than water.
35 ml of toluene is transferred to the separatory funnel and 20 ml of 3M HCl is added, the separatory funnel has been shaken several times. Which layer will contain the lidocaine product, the top or the bottom? >> Lidocaine has tertiary amine group which will be protonated in presence of HCl and will in the salt form which is soluble in water. Therefore it will be in the bottom, aqueous layer.
Two acidic aqueous extracts were combined and 25 nl of 8M KOH solution has been added. This solution has been transferred to the separatory funnel and 15 ml of diethyl ether has been added. The separatory funnel has been shaken several times. Which layer will be the aqueous one, the top or the bottom? >> Bottom will be the aqueous, diethyl ether is lighter than water.
35 ml of toluene is transferred to the separatory funnel and 20 ml of 3M HCl is added, the separatory funnel has been shaken several times. To which layer the second portion of 20 ml of 3M HCl should be added, the top or the bottom? >> Top layer, tolune layer which will have residual compound.
two acidic aqueous extracts were combined and 25 nl of 8M KOH solution has been added. This solution has been transferred to the separatory funnel and 15 ml of diethyl ether has been added. The separatory funnel has been shaken several times.Which layer will contain the lidocaine product, the top or the bottom? >> Now, it is the free base and will be soluble in ether. So, lidocaine will be in upper layer.