Removal of Silyl Ether Protecting Groups
Reaction with acids or fluorides such as tetra-n-butylammonium fluoride remove the silyl group when protection is no longer needed. Larger substituents increase resistance to hydrolysis, but also make introduction of the silyl group more difficult.
In acidic media, the relative stability is:
- TMS (1) < TES (64) < TBS (20 000) < TIPS (700 000) < TBDPS (5 000 000)
In basic media, the relative stability is:
- TMS (1) < TES (10-100) < TBS~TBDPS (20 000) < TIPS (100 000)
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