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Topic: What are the right reagents to use here?  (Read 3802 times)

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Offline sun725

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What are the right reagents to use here?
« on: April 18, 2017, 01:01:40 PM »
I think it should be f and d but I'm not sure at all.  - Hope someone can help.

Thanks in advance.
« Last Edit: April 18, 2017, 01:06:43 PM by Borek »

Offline Babcock_Hall

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Re: What are the right reagents to use here?
« Reply #1 on: April 18, 2017, 04:44:00 PM »
Would you mind providing your reasons?

Offline sun725

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Re: What are the right reagents to use here?
« Reply #2 on: April 18, 2017, 05:18:34 PM »
We are using the Malonic Ester synthesis. We also have to add the elements of CH2COOH to the starting compound.
steps: a, c, d  ? Now when I'm looking at it again ... However, not sure at all. Hope you can provide me with more info?



Offline sun725

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Re: What are the right reagents to use here?
« Reply #3 on: April 19, 2017, 01:49:46 PM »
Isn't there anyone who can answer me?

Offline Babcock_Hall

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Re: What are the right reagents to use here?
« Reply #4 on: April 19, 2017, 02:17:29 PM »
Clearly your initial answer was wrong.  You need to add a total of four carbon atoms, for one thing.  Now let's take your second idea.  If this is going to be a malonic ester type synthesis, you will need to do something to your alcohol to make it an appropriate starting material.  What will you have to do, and how will you do it with these reagents?

Offline sun725

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Re: What are the right reagents to use here?
« Reply #5 on: April 19, 2017, 03:08:06 PM »
And then we'll have to re-esterify. (d, f?)

Offline Babcock_Hall

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Re: What are the right reagents to use here?
« Reply #6 on: April 19, 2017, 03:33:25 PM »
I don't understand your last response.  What is the nucleophile and what is the electrophile in the first step of a malonic ester synthesis?

Offline rolnor

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Re: What are the right reagents to use here?
« Reply #7 on: April 21, 2017, 08:27:20 AM »
To decarboxylate you need to hydrolyse the malonic ester, then esterificate the resulting acid?

Offline Babcock_Hall

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Re: What are the right reagents to use here?
« Reply #8 on: April 21, 2017, 08:32:54 AM »
rolnor,

It seems to me that the malonic ester should be connected to the rest of the molecule before one decarboxylates.  The OP needs to find a way to modify the alcohol first, unless I am missing something.

Offline rolnor

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Re: What are the right reagents to use here?
« Reply #9 on: April 21, 2017, 09:27:12 AM »
Yes, you need SOCl2 first to make the alkylchloride then malonester.

Offline Babcock_Hall

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Re: What are the right reagents to use here?
« Reply #10 on: April 21, 2017, 10:04:35 AM »
@OP, Now that you have been given some generous hints, this problem should be a snap.

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