Ketones - Sanfordchemistrystudentwork

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Ketones
By: Tara and Rhiannon
General Structure
Keto:
A ketone is formed by
the decomposition of a
secondary alcohol in
the presence of a
catalyst at a boiling
point of 550-600
degrees Celsius. The
preparation of a ketone
this way is called a
dehydrogenation
reaction.
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AKA: Alkenols
Enols
◦ These are alkenes with a hydroxyl group
attached to one of the carbon atoms forming
the double bond
◦ The enol is normally unstable, doesn’t survive
long and changes into the keto
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Ketones are highly reactive. The double bond
on the carbonyl group determines ketones
from alcohols and ethers.
A carbon atom across a carbonyl group is
often referred to as an a-carbon and the
hydrogen atoms connected to the center of
an a-carbon are called a-hydrogen.
Ketones with a-hydrogen centers experience
a Keto-enol tautomerism (a chemical
equilibrium between a keto form and an enol)
Reactivity
Oxidation of Ketones
Ketones can only be oxidized under
vigorous conditions using strong oxidizing
agents such as Potassium Permanganate,
Potassium dichromate etc. Oxidation of
ketones are separated by a carbonyl
carbon and a carbon on either side of the
keto group making it a mixture of
carboxylic acid.
2CH3OH -> 2CH2O + 2H2O
Naming

Ketones contain a carbonyl group (C=O)
and are connected to two alkyl groups.
Common names are formed by naming the
two alkyl substituents (which cannot be
hydrogen) connected to the carbonyl group
and by replacing the “ane” ending with
“anone”
Acetone
2-butanone
More examples
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Ketones are used in
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Paint
Adhesives
Printing ink
And cleaners
Everyday products
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http://www.cartage.org.lb/en/themes/scienc
es/Chemistry/Organicchemistry/Families/Som
efamilies/Ketones/Ketones.htm
http://www.tutorvista.com/content/chemistry
/chemistry-iv/oxygen-ii/oxidation-aldehydesketones.php
http://en.wikipedia.org/wiki/Ketone
Text book: Chemistry by Gillespie,
Humphreys, Baird and Robinson.
(accessed Sept.17/09)
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Reference list