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Topic: Organic finals  (Read 6752 times)

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Offline nanotube

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Organic finals
« on: August 25, 2012, 06:09:59 AM »
Hi guys

I've got my finals in organic chemistry (2 Ba Biochemistry) in a few days. I managed to find some
questions from the previous year, but not the answers. (to check my solutions)  ???
So if anyone has some spare time (and want to test their own knowledge), I would really
appreciate if you could solve 1 or few things.

Thx in advance  ;)
« Last Edit: August 25, 2012, 07:09:35 AM by nanotube »

Offline discodermolide

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Re: Organic finals
« Reply #1 on: August 25, 2012, 06:13:48 AM »
Hi guys

I've got my finals in organic chemistry (2 Ba Biochemistry) in a few days. I managed to find some
questions from the previous year, but not the answers. (to check my solutions)  ???
So if anyone has some spare time (and want to test their own knowledge), I would really
appreciate if you could solve 1 or few things.

Thx in adnvance  ;)

Reaction 1 is a Diels-Alder reaction.
What about your answers, it's a bit much to go through!
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Offline Borek

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Re: Organic finals
« Reply #2 on: August 25, 2012, 06:20:03 AM »
Post a question, post what you think is a correct solution - that's the only way we work here.
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Offline nanotube

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Re: Organic finals
« Reply #3 on: August 25, 2012, 06:27:33 AM »
Alright, I'll post my answers in a bit.

Offline nanotube

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Re: Organic finals
« Reply #4 on: August 25, 2012, 07:09:13 AM »
This is what I've got for the first part.

(multi-synthesis will follow in a bit)

Offline rrr_asd

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Re: Organic finals
« Reply #5 on: August 25, 2012, 08:10:11 AM »

Offline discodermolide

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Re: Organic finals
« Reply #6 on: August 25, 2012, 08:15:31 AM »
This is what I've got for the first part.

(multi-synthesis will follow in a bit)

Re-think numbers 2, 3, 5, 6 (structure wrong), 8, 9 (structure wrong), 10, 11, 12

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Offline rrr_asd

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Re: Organic finals
« Reply #7 on: August 25, 2012, 08:41:09 AM »

Offline nanotube

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Re: Organic finals
« Reply #8 on: August 25, 2012, 08:48:23 AM »
2: will all the allylic groups be brominated ?
3 and 10: isn't Friedel–Crafts reaction prohibited with meta-directors ?
6: why ?
8: benzyne elimination-addition is the only one I know to carry out this reaction
9: see image
11: my fault, typo
12: ah yes I see

Offline rrr_asd

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Re: Organic finals
« Reply #9 on: August 25, 2012, 08:49:00 AM »

Offline rrr_asd

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Re: Organic finals
« Reply #10 on: August 25, 2012, 08:51:23 AM »
This is what I've got for the first part.

(multi-synthesis will follow in a bit)

Re-think numbers 2, 3, 5, 6 (structure wrong), 8, 9 (structure wrong), 10, 11, 12



Numbers 2, 9 are correct.

Offline rrr_asd

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Re: Organic finals
« Reply #11 on: August 25, 2012, 08:55:01 AM »

3 and 10: isn't Friedel–Crafts reaction prohibited with meta-directors ?


Yes, it is.

Offline discodermolide

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Re: Organic finals
« Reply #12 on: August 25, 2012, 08:58:49 AM »
2: will all the allylic groups be brominated ?
3 and 10: isn't Friedel–Crafts reaction prohibited with meta-directors ?
6: why ?
8: benzyne elimination-addition is the only one I know to carry out this reaction
9: see image
11: my fault, typo
12: ah yes I see


Number 9 is incorrect you start with an di-ester and alkylate the middle carbon with allyl bromide.
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Offline nanotube

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Re: Organic finals
« Reply #13 on: August 25, 2012, 09:29:14 AM »

Number 9 is incorrect you start with an di-ester and alkylate the middle carbon with allyl bromide.

So basicly the first solution is correct ?

Offline discodermolide

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Re: Organic finals
« Reply #14 on: August 25, 2012, 09:30:23 AM »

Number 9 is incorrect you start with an di-ester and alkylate the middle carbon with allyl bromide.

So basicly the first solution is correct ?
no because you missed out a carbon atom it is an allyl bromide.
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