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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: jay1227 on June 27, 2007, 09:10:05 PM

Title: benzocaine synthesis
Post by: jay1227 on June 27, 2007, 09:10:05 PM

we made benzocaine in lab with an acid-catalyzed synthesis, and a base was used to precipitate it out of the solution.
does the base neutralize the excess acid used in the synthesis, which makes the reaction favored to the right in making the benzocaine product?

Title: Re: benzocaine synthesis
Post by: Mitch on June 28, 2007, 02:01:17 AM

See #1 in the signature.

Title: Re: benzocaine synthesis
Post by: Yggdrasil on June 28, 2007, 03:54:04 PM

Benzocaine is a base.  In acidic conditions, will it be charged or uncharged?  In basic conditions, will it be charged or uncharged?  What is the solubility of charged organic molecules in water?  What is the solubility of uncharged organic molecules in water?

Title: Re: benzocaine synthesis
Post by: jay1227 on July 02, 2007, 01:47:37 AM

writing out the mechanism for the benzocaine synthesis, i only see that it is similar to an esterification reaction, and that there is an acid catalyst, but i dont see what adding a base can do to the benzocaine product to let it precipitate out of solution

if benzocaine is basic, then in acidic conditions it will have at least a +1 charge, and since charged organic molecules are more soluble in water, the benzocaine is dissolved or suspended in the water...adding the base removes this positive charge on benzocaine, making it less soluble?

Title: Re: benzocaine synthesis
Post by: Yggdrasil on July 02, 2007, 03:02:07 AM

Quote from: jay1227 on July 02, 2007, 01:47:37 AM

if benzocaine is basic, then in acidic conditions it will have at least a +1 charge, and since charged organic molecules are more soluble in water, the benzocaine is dissolved or suspended in the water...adding the base removes this positive charge on benzocaine, making it less soluble?

Correct.