Chemical Forums
Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: nikon50bigma on March 07, 2013, 05:12:50 PM
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I'm like freaking out. Please help.
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You have to show your attempts at solving the question to receive help. This is a forum policy.
Some steps look obvious even to me :o
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Hi,
Sorry this was my first time using the forum. Thanks for your reply and informing me though.
Here is what I thought the steps were:
A. H3O+ and heat
B. PBr3
C. NaBH4
D. (CH3)3CO-
E. Mg, Ether
F. PCC
G. NaNH2
I'm sorry I'm just not very good at this subject :-(
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I'll give you a few hints to start off.
B is a bromination reaction. PBr3 is not one of your reagents, that's PPh3.
E is an oxidation of alcohol to aldehyde, right? So you will need an oxidizing agent like PCC.
D is deprotonation of an alkyne, what is a strong enough base to rip off a proton from an alkyne?
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Thanks so much for your reply! Your a god send!
PBr3 is a reagent available to use, so can I used that or do I need to use the PPh3?
For D. isn't (CH3)3CO- that appropriate because that can act as a base?
Thanks!
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Oh sorry I was looking at PPh3 and didn't notice PBr3. PBr3 is used to convert alcohols to alkyl bromides so look for another bromine source.
To depronate alkynes you need a very strong base, such a strong base would be NaNH2.
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Hi!
Thanks for the reply!
I think I got the hang of it now :)
How do this sound?
A. H3O+ and heat
B. Br2, CH2Cl2
C. NaBH4
D. NaNH2
E. PCC
F. H3O+ and heat
G. H3O+
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C. NaBH4
No, google alkyne synthesis.
For (f), you need to mix the reagents, wait for them to react and then do a protic workup (H3O+). Not sure what the best answer to the question is because if you add acid at the beginning the reaction will not proceed (because you will just protonate the nucleophile).
G. H3O+
No.
Alcohol :rarrow: ketone - google it!