puzzledstudent
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addition to alkenes
hello. i'm back. thank you to drunkguy who has given great help in the past. i again need help with homework regarding addition to alkenes. just to
let you all know, this is homework 8 of 10. so there'll be 2 more homeworks on which i will ask for double-checking. anyone, please be so kind as to
check my answers. my answers and links to the homework follow:
page 1:
http://img.villagephotos.com/p/2006-10/1223233/ochemhw8p1.JP...
page 2:
http://img.villagephotos.com/p/2006-10/1223233/ochemhw8p2.JP...
My answers:
1-B
2-B
3-A
4-A
5-A
6-A
7-B
8-A
9-D
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guy
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2 - A, markinokov rule
9 - C?
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Drunkguy
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1. Hydroboration - anti Markovnikov (opposite from oxymercuration)
2. (b) Tertiary carbocation intermediate is stabilized
6. (a) seems obvious enough except that the carbocation will tend to undergo a 1,2-hydride shift so it's actually (b).
8. This is weird. I agree that (a) seems correct.
9. (c) Alkenes are hydrolyzed by aqueous acid.
[Edited on 6-11-2006 by Drunkguy]
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Sandmeyer
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Please, homework help is intended for Beginings Forum -- post there!
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guy
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| Quote: | Originally posted by Drunkguy
Actually, 4 is (b). |
Why would 4 be B? It would be a straight molecule in a plane and according the markinokov rule it will only have one isomer.
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Nicodem
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4 is C.
The resulting compound, 3-bromo-3-methylpentane, is "an achiral compound". Thus the answer can not be neither B nor A, much less D. The confusion
obviously arises from the lack of the insight that the addition creates symmetry around the prochiral site (another Et group forms, undistinguishable
from the existing).
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Sandmeyer
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Damn, I wish I went to scool in America, they actually provide you answers on the tests - cool!
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guy
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| Quote: | Originally posted by Sandmeyer
Damn, I wish I went to scool in America, they actually provide you answers on the tests - cool! |
America does the worst in science! Probably because of religious fundamentalism.
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dapper
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or because we cheated all through general and organic chemistry.
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