[arom58]

I've been trying to carry a Suzuki rxn out on an aryl bromide and a tbutyldiphenylsilyl- protected phenyl boronic acid but I have read ( Tetrahedron Utters, Vol. 38, No. 2, pp. 187-190, 1997) that the protecting group would not survive alkalinity of the reaction. The protection on phenolic OH is absolutely necessary and it must also get deprotected afer the Suzuki coupling easily. TBDPS and TOM look auspicious for the deprotection step but I first need to get away with their base sensitivity.

[gfunk]

I remember reading how TBDPS was quite stable in acidic conditions (about 5 million times that of TMS), but never looked into its alkaline stability.  If you get a protecting groups book (like Kocienski's) it'll give you the relative stabilities of the silyl ether protecting groups in acidic and alkaline conditions.  If I remember correctly, TIPS (triisopropyl silyl-) is one of the more stable silyl protecting groups in alkaline conditions.

I left my Kocienski book in my lab, but the Wikipedia article replicates the exact same format as the book.  In fact, I'm sure it's a shameless ripping:

http://en.wikipedia.org/wiki/Silyl_ether

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)

[arom58]

Thank you very much buddy. It's been very helpful

[gfunk]

No problem, hope it helped! :-)