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Topic: primary and tertiary alcohol- which will be deprotonated by a base?  (Read 2765 times)

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Offline trishasales714

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Structure: cyclopentane with one carbon having 2 alcohols - one is tertiary (OH directly attached) while the other primary alcohol is 2 carbons away. If this was reacted with NaOH, which of alcohols will be deprotonated? How can we deprotonate just the primary alcohol?

Offline wildfyr

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Re: primary and tertiary alcohol- which will be deprotonated by a base?
« Reply #1 on: April 16, 2017, 07:20:30 PM »
You can't with NaOH. But you could do some selective protection chemistry. Hm... this is a little tough. You could probably get decent selectivity protecting just the primary alcohol with 1 equivalent TMS. Isolate, then protect the tertiary one with TBDMS. Water or a little weak acid will only deprotect the TMS. Then expose it to base. TBDMS ethers are reasonably base stable as long as its not highly concentrated/hot NaOH. Boom.

Offline Babcock_Hall

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Re: primary and tertiary alcohol- which will be deprotonated by a base?
« Reply #2 on: April 17, 2017, 08:20:08 AM »
@OP,  It is a forum rule that you show your attempts or give your thoughts before we can help you.  Here is a question to get you started:  Are all alcohols equally acidic?

Offline wildfyr

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Re: primary and tertiary alcohol- which will be deprotonated by a base?
« Reply #3 on: April 17, 2017, 08:37:07 AM »
I feel I should addend the beginning of my response: It would be difficult, finicky, and incomplete to directly deprotonate just one directly. OP should try to guess why.

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