ADA 2009 sample test (#71, 89, 99)

[jhc83]

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I just took the ADA 2009 sample test.
I got these three problems wrong in the OC section...
Can someone please explain to me how to solve these problems?
Thanks in advance!

 

[diene]

I just took the ADA 2009 sample test.
I got these three problems wrong in the OC section...
Can someone please explain to me how to solve these problems?
Thanks in advance!

For the second one, step 1 converts NO2 to NH2..step 2 converts NH2 to a chloride...step 3, chloride being a good leaving group, leaves and is replace by CN. Check out this site for another example of the 2nd step..I had never seen NaNO2 with HCl before. http://instruct.westvalley.edu/harrison/chem12B/notes/Chap19 chem12B.pdf

for the last question, the question is erroneous because they ask for napthalene, which is supposed to have 2 rings, yet they give an image of 3 rings.....I would just know how to solve this, but disregard the answer.

 

[lutopie0730]

I think the the answer for the first question is the last one. First, get rid of B and C cuz they dont make sense at all. Second, tertiary amine is not reactive and secondary amine is a nucleophile. Therefore, a ring opening of epoxide seems more reasonable to me. Wish that i got it right though 😀

 

[njdoc327]

for the second one, it is the formation of a diazonium salt, correct? so the answer would be C? and yes for the third one, diene is right. if it is two rings though, there would be two products. and with three rings, its 3 products.

 

[dentistaporfavor]

Isn't Br- a better LG group than Cl-? Why would CN replace Cl and not Br?