TBDMS protecting group

TsOH, DMF, Mc2C(OMe)2, 24 h. This method has become one of the most popular methods for the preparation of acetonides. It generally gives high yields and is compatible with acid-sensitive protective groups such as the TBDMS group. 

The synthesis of 5-phosphono-l,2,4-triazolin-3-one 137 began with the low-temperature metalation and phosphorylation (77) of the f-butyldimethylsilyl (TBDMS)-protectedlV-benzyl-tiiazolinone 134. The phosphonate diester 135 was obtained ter the silyl protecting group... 

A variety of alcohols, protected as t-butyldimethylsilyl (TBDMS) ether derivatives, can be rapidly regenerated to the corresponding hydroxy compounds on alumina surface using MW irradiation (Scheme 6.8) [42], This approach prevents the use of corrosive fluoride ions that are normally employed for cleaving the silyl protecting groups. 

The problem of the rather moderate yields of ene-adducts 177 was solved when the more robust TBDMS protecting group was employed. Using reagent 180 instead of 171, a smooth ene-reaction occurred, affording the silyl enol ethers 181 in improved yields (Scheme 13.63). 

Martin periodinane to deliver the desired key intermediate, ketone 208. The total synthesis of 181 was finalized in two more steps (49% overall yield) by removal of the acetal and the MEM protective group with simultaneous formation of the desired intramolecular ketal 216, followed by cleavage of the Cl 1 TBDMS ether and in situ oxidation with IBX. The highly complex secondary metabolite 181 was thus accessed in 16 linear steps starting from 210 with an impressive 14% overall yield (Fig. 36). 

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