TBDPS

MesSi- and iPrsSi groups can be selectively removed in the presence of TBS or TBDPS groups. 

Benzyl, allyl, methyl, THP, TBDMS, and TBDPS ethers are all stable to these conditions. A primary MEM group could be selectively removed in the presence of a hindered secondary MEM group. 

TsOH, MeOH, 25°, 1 h, 94% yield.TBDPS ethers are not affected by these conditions. ... 

Et2AlCl, CH2CI2, 3 min, 70-85% yield.This method was used to remove the trityl group from various, protected deoxyribonucleotides. The TBDPS group is stable to these conditions. 

The greater bulkiness of the TIPS group makes it more stable than the /-butyldi-methylsilyl (TBDMS) group, but not as stable as the /-butyldiphenylsilyl (TBDPS) group to acidic hydrolysis. The TIPS group is more. stable to basic hydrolysis than... 

Pyridinium p-toluensulfonate, EtOH, 22-55°, 1.2-2 h, 80-92% yield. These conditions were used to leihove cleanly a TBDMS group in the presence of a TBDPS group. 

Bu2SnO, PhCH3, heat, 10 h with H2O removal, then Bu4N Br , TBDPSCl, heat, 8 h. This method was used to introduce one TBDPS group on one of two primaiy alcohols in 92% yield. 

LiAlH4 has resulted in the cleavage of a TBDPS group, but this is not general. TBDPS ethers are generally not affected by LiAlH4. 

NaH, HMPA, 0°, 5 min H2O, 83-84% yield. These conditions selectively cleave a TBDPS ether in the presence of a t-butyldimethylsilyl ether. 

Dibutyl-2-stanna-l,3-dithiane, Bu2Sn(OTf)2, CICH2CH2CI, 35 1 h, 77-94% yield. TBDMS, TBDPS, THP, and OAc groups are not affected by these conditions. 

ZnBr2, MeOH, 100% yield. TIPS and TBDPS ethers are stable to these conditions. 

Methanol, CCI4, ultrasonication, 40-50°, 90-96% yield." Phenolic TBDMS and TBDPS ethers are stable. 

AI2O3, H2O, hexanes, 81-98% yield. These conditions are selective for the primary derivative. TBDPS and TMS ethers are also cleaved. The use of alumina in a microwave oven is also effective (68-93% yield). ... 

PdO, cyclohexene, methanol, 30 min for a primary ROH, 90-95% yield. Secondary alcohols require longer times. The primary TBDPS and TIPS groups are cleaved much more slowly (18-21 h). Benzylic TBDMS ethers are cleaved without hydrogenolysis. ... 

AcBr, CH2CI2, it, 20 min, 90% yield. These conditions convert the TBDMS ether into the acetate. Benzyl and TBDPS ethers are stable, except when SnBr2 is included in the reaction mixture, in which case these groups are also converted to acetates in excellent yield. ... 

BF3 Et20)-Bu4N F. This reagent is selective for TBDMS ethers in the presence of TIPS and TBDPS ethers. ... 

Yb(OTf)3, MeOH, 0-25°, 92-99% yield. Acetates, benzoates, THP, TBDMS, TBDPS, and MEM ethers are not affected by this reagent. ... 

EtO)3SiCl, Nal, CH3CN, CH2CI2, —5°, 0.5 h, 74% yield. This method was reported to work better than TMSI. TBDPS groups were not affected by this reagent. 

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