Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: arvind1990 on May 25, 2006, 01:50:45 PM
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How do you convert acetaldehyde to
a)Butan-2-one b)Butan-1,3-diol c)But-2-enal d)Butanol e)Butanoic acid
f)But-2-enoic acid.
write the structures of the expected products of Aldol condensation:
a)2-methtylpentanal b)cyclohexanone c)1-phenylacetaldehyde d)phenylpropanone
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Well, the aldol condensations are straightforeward. Look up 'aldol condensation' in a book.
What are your ideas so far on the synthesis of the first ones? Show some of your own input.
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I don not have any idea in the synthesis of the first ones.
I think for the synthesis of( a),we can use cross aldol condensation
ie.,CH3CH0 + CH3COCH3.
I donot have any ider other than this.
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Can anyone help me with those conversions(mentioned above).
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I don not have any idea in the synthesis of the first ones.
I think for the synthesis of( a),we can use cross aldol condensation
ie.,CH3CH0 + CH3COCH3.
I donot have any ider other than this.
yes, that aldol reaction following dehydration will give CH3COCH=CH2, you can then use catalytic hydrogenation to hydrogenate the C=C
b) same reaction, but do not dehydrate the aldol product (use very dilute base), and reduce the carbonyl with eg. LiAlH4
c) This one is just an aldol self-condensation, followed by dehydration
d) is c) followed by hydrogenation of the C=C, and reduction of the carbonyl.
e) is c) followed by hyrogenation of the C=C, and then oxidation of the carbonyl
f) is e) but without the hydrogenation step
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Hi,
Thank You for your reply. Can you say how to dehydrate the aldol formed between the reaction od CH3CHO and CH3COCH3 i.e., how you got the product CH3COCH=CH2
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Sorry, I have made a mistake,
For a) EtLi , then oxidise to ketone. This might be a bit dodgy due to the basicity of the EtLi.
for b) Aldol self condensation, followed by reduction of the carbonyl