Example reaction showing Sn1 mechanism where substrate with six membered ring forms five membered ring product via alkyl shift.
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@syedhassan1583 жыл бұрын
Why would we have not done the methyl shift and make a tertiary carbocation and the six membered ring is more stable than five membered one?
@davecampbell8926 жыл бұрын
Thank-you for the great video :) I have one question, why doesnt the H20 group on the final step act as a leaving group? Only the hydrogen pops off which is different from other videos
@kristenscopino74855 жыл бұрын
I know this is an old question, but I believe it is because if the (-OH2)+ group left it would reform the carbocation. Carbocations are pretty unstable compared to the (-OH2)+ which gets deprotonated really quickly into the stable -OH group.
@MultiChantal224 жыл бұрын
2:28 He said there's a proton transfer, so I assume it's just like any other video (where the lone pair in other H2O attack the proton in the H2O+ part of final product and cause the H to pop out and leave behind the final product). He just writes is as -H+ instead of writing the whole proton transfer mechanism.
@astic42543 жыл бұрын
Think about it...after deprotonation oh the H2O, to further stabilise the molecule of oxygen, the product became an OH attached to an R group (so an alcohol/hydroxyl group). A hydroxyl group is not a good leaving group, as it is a weak base, and to have a strong leaving group it must be a strong base. If it leaves, it will have a formal negative charge, hence becoming an unstable hydroxide anion.
@tairademisheva32306 жыл бұрын
doesnt heat make the mechanism E1?
@anupamsingh92514 жыл бұрын
Why would we have not done the methyl shift and make a tertiary carbocation and the six membered ring is more stable than five membered one?
@l052_jeeveshpathak84 жыл бұрын
i also have the same question that if we were not given the final product then we would make a six membered ring.