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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: zerofreak on January 07, 2011, 11:48:00 AM

Title: Organic chemistry help please.!
Post by: zerofreak on January 07, 2011, 11:48:00 AM
give the names and formulate of the two compounds formed wen the ester ethyl propanoate is hydrolysed.
Please answer with steps. Thanks in advance. :D
Title: Re: Organic chemistry help please.!
Post by: sjb on January 07, 2011, 12:48:31 PM
give the names and formulate of the two compounds formed wen the ester ethyl propanoate is hydrolysed.
Please answer with steps. Thanks in advance. :D

Well, depends partially on conditions, but what are the two components of any ester hydrolysis?
Title: Re: Organic chemistry help please.!
Post by: nezva on January 07, 2011, 01:44:13 PM
hydro- :  pertaining to water or fluid.
-lysis :    from Latin lysis, from Ancient Greek λύσις (“‘loosening’”)
Hydrolysis - "breaking apart with water"

This article on Fischer Esterification is very useful for the more in-depth information of esters:
http://www.organic-chemistry.org/namedreactions/fischer-esterification.shtm

An ester is traditionally formed by dehydration of two molecules: a carboxylic acid and an alcohol.  Dehydration  yields larger molecules and can be thought of as the reverse of hydrolysis, which results in smaller molecules.  Carboxylic acids are named as such since they can readily lose a proton (H+) under relatively mild conditions.  Alcohols do NOT lose protons readily and have pka's closer to that of water.  For the -OH to be removed from an acohol it must be first protonated (by the carb. acid in this case) to make -OH+. Water is a much better leaving group than -OH.

Simple answer (if you don't like learning):
From the IUPAC naming system,
the carboxylic acid part of the ester ends in -oate  
Since only the alkyl chain moeity of the alcohol is attached to the ester, the aklyl chaing is placed before the -oate word.
Title: Re: Organic chemistry help please.!
Post by: sjb on January 07, 2011, 04:25:13 PM
So which acid and alcohol do you use to make ethyl propanoate?
Title: Re: Organic chemistry help please.!
Post by: Grundalizer on January 07, 2011, 09:45:49 PM
ethanol and propanoic acid
Title: Re: Organic chemistry help please.!
Post by: orgstudy on January 10, 2011, 09:25:13 AM
You know your reaction should be either acid or base catalyzed!!!

products will be: Propanoic acid & ethanol.

Mechaism: http://www.chem.ucalgary.ca/courses/351/Carey5th/Ch20/ch20-3-3-1.html (http://www.chem.ucalgary.ca/courses/351/Carey5th/Ch20/ch20-3-3-1.html)