Skip to main content

Hydrolysis of carboxylate to carboxylic acid

Example of a hydrolysis reaction from carboxylate to carboxylic acid, drawn by myself.

The reaction shown is an example of a common hydrolysis reaction used in organic chemistry. 
The ester compound on the left (carboxylate moiety), is usually dissolved in 1,4-dioxane. Then, NaOH aqueous solution is added.

 Conditions are dependent of the type of compound. 
Several conditions can be used:
- 80 °C, 2 M NaOH, if compound is extremely stable, these are harsh conditions.
- 80 °C, 1 M NaOH 
- 60 °C, 2 M NaOH 
- Room temperature (RT), 2 M NaOH 
- RT, 1 M NaOH

 If the compound is susceptible to degradation or is unstable, use room temperature and a low molarity of NaOH. It all depends on the compound of course, and often knowledge is obtained by trial and error. It is advised to start with the least harsh conditions.

 When hydrolysis is complete, isolation of the final compound is done by evaporating the solvent (1,4-dioxane), acidify with HCl or an ion exchange resin, and filter off the precipitation. Dry the obtained solid and analyse.

Comments

Post a Comment

Popular posts from this blog

Alkynen: Elektrofiele additie

Elektrofiele additie: Waterstofhaliden op alkynen Voorbeeld van waterstofhaliden: HCl, HBr, HF, HI Gebruik van één equivalent waterstofhalide met alkyn (dus 1:1 geen overmaat geen tekort) Bij een overmaat aan het waterstofhalide zal een tweede reactie plaatsvinden op het gehalogeneerde alkyn, ter vorming van een geminaal regioisomeer.
Post a Comment
Read more

Coca-Cola: Life - myth or truth?

"Coca-Cola Life" Recently the Coca-Cola company released a new beverage: the Coca-Cola Life drink. It should contain less sugar than the normal Coca-Cola drink; a part of the sugar is replaced with the recently approved sweetener from the Stevia plant (stevioglycosides). It's being sold as a 'natural' drink, but those stevioglycosides are as natural as the chemical sweetener aspartame found in Light and Zero drinks. However it is true that the amount of sugar is much lower (being reported as 33%, some say it's around 20%); yet approximately still 3-4 sugar cubes / 33 cl can (5-6 in a normal can). I bought it myself and found that the flavor has not really changed from the original Coca-Cola, however it does taste more "flat" - but definitely true it yourself. The outside of the can has the colour green. I personally do not associate this "healthy - natural" colour with Coca-Cola, but it's growing on me. In sum...
1 comment
Read more

Alkylhalides: Substitution reactions 6 (Sn1)

Alkylhalides: Substitution Nucleophile substitution reaction ( Sn1 reaction ) Sn1 side reactions I will now discuss some side reactions that can occur when a Sn1 reaction takes place. Carbocation shift Illustrated in the scheme below: Benzyl- and allylhalides  Benzyl- and allylhalides can undergo Sn1 AND Sn2 reactions. How to distinct them? Sn1 conditions: protic solvent and by adding a weak attacking nucleophile. Note: Benzyl- and allylhalides easily undergo Sn1 reactions, because their carbocations are very stable. Sn2 conditions: aprotic solvent and by adding a strong attacking nucleophile. Note: tertiary benzylhalides and tertiary allylhalides will NOT undergo a Sn2 reaction because of the steric effects (see chapter Sn2 reaction blogposts). Sn2 reaction examples Sn1 reaction examples Sn1 and Sn2 reactions in biology, nature and medicines S-Adenosyl methionine This is a biological methylating agens, also known as SAM . It is a frequen...
1 comment
Read more