View Full Version : O chem road map 3


utdent20
07-16-2008, 12:42 PM
a primary bromide undergoes (CH3)3CO-Na+ giving a double bonded Carbon, is this always the case or with secondary it would be different?
Also O3/ZnH20 will always provide with a C=0 and =0? is ozonlysis known as the same thing or is that a separate reaction.?

JMCougar
07-16-2008, 01:04 PM
The reaction you're talking about on roadmap 3 is actually a tertiary bromide, but that's not really what matters here since you have tert-butoxide (a great base but poor nucleophile) hence E2 so carbocation stability doesn't come into play. Because tBuO- is so big, it's going to grab the least sterically-hindered H... one from the methyl group. Methylene is formed and Br leaves. tBuO- will always take the least hindered H (unless there is not an anti-periplanar H available... which happens in lots of questions involving cyclohexane... just draw chairs if you need to visualize!)

O3/ozonolysis are one and the same.

Good luck and hope that helps!

wifi08
07-18-2008, 01:33 PM
that is ozonolysis but make sure that catalyst is there or you could end up with a CO2
secondly even with a secondary it will dehalogenate because this is a very strong base. the reason it was shown as primary was to illustrate a hoffman elimination