Alright, so is this one good?


For the second one, I'm still struggling with it. Is this a step in the correct direction, at least? Is what I did in the middle legal?


/Good grief, sorry for the big pictures this time.

This post was edited by Micrographia on Jan 18 2015 05:21pm

The first drawing looks pretty good. Remember this SN2 inverses the chirality, although in this case the 2-bromopropane is not chiral so the stereochemistry is irrelevant here.


Just to be clear, the carbocation is stabilized by the nitrate and the solvent's polarity. So the second drawing is not quite right. Perhaps some of the reactants may be better relocated. I think having:
2-Bromopropane + ethanol
moved to the the left would be better. Also, write in + AgNO3 just above the arrow may help. A pinch may suffice in fact. This reagent promotes the stabilization of the carbocation, so the reaction may proceed forward.

Another point of precision: Both alkyl products are the same in this one case because the 2-Bromopropane is not chiral. So if I were to draw this mechanism, I would have a single product plus HNO3 plus AgBr(s) and I would explain that a racemic mixture would be obtained if a chiral alkyl is used to begin with.

You're definitely moving in the right direction.

This post was edited by Dmon_Hunter on Jan 18 2015 06:53pm

That is a huge help.
I was just introduced to these concepts last week and after that first lecture I, admittedly, felt pretty clueless. Visually working through these problems has greatly helped my understanding. Thank you!

I'll post my final mechanism tomorrow for you to look over, if that's alright. That'll give me time to read some more from this chapter and to ask any final questions before classes start back up this week.

This post was edited by Micrographia on Jan 18 2015 07:04pm

Alrighty. I moved the reactants over, like you had suggested. Also, the racemic mixture point was really helpful. It does cause me to question how to draw that final product, though. Is the product shown in this picture correct? Should there be any stereochemistry shown?
+ Does the middle section look alright? I'm not sure if there's a better way to show that.