Confused on Orgo Destroyer Question

[americanpierg]

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CH3CH2CH2OH ---> heat/H3O ----> BR2/CCl4 ----> 1) 3NaNH2,NH3/ 2)H2O ----> HgSO4/H2SO4, H2O

I can get to the BR2/CCl4 part, but I don't know why they used 3 eqv. of NaNH2,NH3 to remove the 2 bromines. Wouldnt 2 be enough to remove the 2 bromines, and the third would therefore remove the terminal hydrogen from the terminal alkyne (CH3CHCH) and make it CH3CHC- Na+ ???

 

[Snowy19]

It's hard to know visualize the question on the forum. Can you post the question number?

 

[kkmaths90]

hmm check and see if NaNH2, NH3 is only two equivalent

 

[wantVCUdental]

i see your point, but i don't think it makes a huge difference, it's in water and the deprotonated alkyne probably exist in equilibrium with the protonated alkyne. when you oxymercurate it, it's still fine.

 

[americanpierg]

It's hard to know visualize the question on the forum. Can you post the question number?

Number was 71. This is 2008 edition. Yes it says 3 eqv of NaNH2, NH3. I guess the extra 1 eq is destroyer's way of making the question tricky (?) since the H will be replaced with the H2O anyways. This will never show up on the DAT but I was jw anyways. Thanks.

 

[dentrilla]

Just for anyone else's reference its question 91 in destroyer 2009 🙂