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Chemistry Forums for Students => Organic Chemistry Forum => Topic started by: Polly Murs on December 10, 2011, 02:21:58 PM

Title: Deprotection of silyl ethers with TBAF
Post by: Polly Murs on December 10, 2011, 02:21:58 PM
I've left this going over the weekend, but I've read that the deprotection can take as little as 1.5h

is it possible to leave this going for too long, i.e. 72h?!!
Title: Re: Deprotection of silyl ethers with TBAF
Post by: discodermolide on December 10, 2011, 03:45:58 PM
I've left this going over the weekend, but I've read that the deprotection can take as little as 1.5h

is it possible to leave this going for too long, i.e. 72h?!!

It should be ok, as long as your product is stable to the reaction conditions and the system is dry.
Title: Re: Deprotection of silyl ethers with TBAF
Post by: Polly Murs on February 01, 2012, 08:33:10 AM
can anyone suggest a good TBAF work-up?
Title: Re: Deprotection of silyl ethers with TBAF
Post by: discodermolide on February 01, 2012, 10:21:58 AM
can anyone suggest a good TBAF work-up?

Partition between isopropyl acetate and water.
Title: Re: Deprotection of silyl ethers with TBAF
Post by: OC pro on February 01, 2012, 01:50:09 PM
In my protodesilylations, I normally use THF straight out of the can (means: the system must not be anhydrous) and the 1M solution of TBAF in THF at room temperature. 1.2 equivalents do the job.
You can also simply evaporate the solvent and purify the residue on silica gel. No aqueous work-up is necessary.
Title: Re: Deprotection of silyl ethers with TBAF
Post by: discodermolide on February 01, 2012, 04:25:05 PM
In my protodesilylations, I normally use THF straight out of the can (means: the system must not be anhydrous) and the 1M solution of TBAF in THF at room temperature. 1.2 equivalents do the job.
You can also simply evaporate the solvent and purify the residue on silica gel. No aqueous work-up is necessary.

An aqueous work up is always good to do, and requires little effort as part of the purification process.
Title: Re: Deprotection of silyl ethers with TBAF
Post by: Zainb on February 02, 2012, 04:37:45 AM
You can use acid resin and calcium carbonate, followed by filtration and evaporation.


more details in the full paper:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2519602/ (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2519602/)