prsndwg

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Apr 19, 2009
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Hi,

I am confused about #111 answer b of 2009 destroyer Orgo. Why are the switching it twice? shouldnt once be enough?

Thanks

Here i tried to draw it out.. y there is a need for second swtich?
ps. sorry for the small size.. i had to resize it so they will let me upload it.
 

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Last edited:
May 15, 2009
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Hi,

I am confused about #111 answer b of 2009 destroyer Orgo. Why are the switching it twice? shouldnt once be enough?

Thanks
At some point it would be a good idea to mention what the question is asking you rather than posting the # alone.
 
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prsndwg

prsndwg

7+ Year Member
Apr 19, 2009
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2009.. its a drawing and I cant post it here..
 

Tommy43087

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If you switched it only once it would have been completely invalid, and a different configuration than it really is. Dont only depend on the switching substituents rule, it can get you confused, rotate the molecule in your head into the conformation where the Hydrogen or the lowest priority substiuent would be pointing away.
 
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prsndwg

prsndwg

7+ Year Member
Apr 19, 2009
1,115
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Status
Pre-Dental
Thanks,
but what is wrong with the 1st switch? I am not understanding what is wrong about it? isnt H on the back?
If you switched it only once it would have been completely invalid, and a different configuration than it really is. Dont only depend on the switching substituents rule, it can get you confused, rotate the molecule in your head into the conformation where the Hydrogen or the lowest priority substiuent would be pointing away.
 

Tommy43087

10+ Year Member
7+ Year Member
Feb 18, 2009
673
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Thanks,
but what is wrong with the 1st switch? I am not understanding what is wrong about it? isnt H on the back?
Yea H is in the back but remember when you switch only once you switch R to S and S to R, that why from what i remember with that switch rule you must switch twice. I personally never use that rule because it can get you in to trouble some places, if you can try visualizing it or even better switch it around then visualize what you came up with to check it.
 
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prsndwg

prsndwg

7+ Year Member
Apr 19, 2009
1,115
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Pre-Dental
got it..perfect..thanks

Yea H is in the back but remember when you switch only once you switch R to S and S to R, that why from what i remember with that switch rule you must switch twice. I personally never use that rule because it can get you in to trouble some places, if you can try visualizing it or even better switch it around then visualize what you came up with to check it.