organic chemistry II

[Kigs!]

Any chemistry junkies out there? my current class was presented with figuring out the retro-synthesis of this problem and it's been bugging me for the last couple of days. Any help would be apprecieated... having a hard time trying to figure out how it goes from 3D to planar.

 

[ninja120]

I think you teacher is drawing planar because it is easier to draw.

 

[ninja120]

3D can show you stereo chemistry and alignment of atoms, while planar will not shows the stereochemistry unless you use dotted lines and wedges representing atoms going in and out of the page.

 

[ninja120]

Just a quick question, are you sure that second drawing is correct?

 

[Kigs!]

hey ninja,

yeap i assumed that's why he drew it that way too. the 2nd drawing is correct, why?

 

[ninja120]

well when looking at any H30 reactions they always tend to form and OH group but in the final product there is none.

 

[Kigs!]

ah, I think the professor just indicated the final step of acid dehydration. We just had to figure out the rest of the synthesis reagents needed to get to that final step.

 

[ninja120]

So i am guessing you figured out the rest of your steps to you synthesis?

 

[Kigs!]

? no, thus why I posted the problem on here lol. Most synthesis problems are easy if you do it retro, but this one just got me stumped.

 

[ninja120]

Do you have a planar drawing of first and final? I hate looking at it like that

 

[ninja120]

lol formation of the double bond and removal of the epoxide is easy. But the shift of the O is wierd

 

[ninja120]

Truthfully I dont know how the change in ring shaped occured. Cause orginally the 2 cyclohexanes had 2 similar bonds but in the end it ended up with 1.