TBDMS Chloride (Hiding the alcohol)

Just like boc protects amines, TBDMS protects alcohols.

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TBDMS chloride will protect alcohols. The silicon-oxygen bond is pretty strong, and the silicon-fluorine bond is even better. This provides a protecting group that's pretty robust - fluoride reagents are typically used for removing the silyl ether. More on that shortly...

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how to deprotect O-TBDMS????

By Narasimharao (not verified) on 22 Feb 2011 #permalink

It can also protect acetylenes, or at least make them more soluble and amenable to a little crystal engineering magic. Although...the awkward shape can also be sort of a hindrance there...you get a bit of disorder. :(

The magic fluoride reagent is [tetra-n-butyl] ammonium hydrogen bifluoride, (HF2)-. Whether you are dissolving stone or cleaving Si-O, it goes where mere F- lacks cooperation. Aqueous surface tensions can be high (dissolving stone). A drop of Dawn dishwashing liquid or a Fluorad surfactant helps.

Oh my god! I just did a TBDMS protection of a primary alcohol using this very reagent (like 4 minutes ago). So weird...

By Vince Noir (not verified) on 07 Oct 2008 #permalink

Also, it isn't that stable. Some 90% TFA or formic acid, or even 1% HCl in dry methanol will pop it right off. Convenient when you want to remove it with another acid-labile group, a pain in the butt for orthogonality!

By Vince Noir (not verified) on 07 Oct 2008 #permalink

Xuse me, but some of your post are too condensed for a non chemist to be of interest. Perhaps the compounds are really too arcane for use outside the lab...