3- Triethylsilyloxy

From (S)-4-(tert-butyIdimethylsilyloxy)-2-cyclopentenonc ethyl (lK,5S)-5-(teri-butyldimethyIsilyloxy)-3-triethylsilyloxy-2-cydopenteneacelate yield 92% 90% ee... 

CjjHjoOioSi 115437-18-8) see Paclitaxel [(triethylsilyl)oxy]acetic acid ethyl ester (C oH220jSi) see Paclitaxel c -3-(triethylsilyloxy)-4-phenyl-2-azetidinone (Ci3H23N02Si) see Paclitaxel trifluoroacetic anhydride... 

Propene 3-Phenyl-l.l,2-trifluoro-3-triethylsilyloxy- ElOb, 420 (SiR3 -> CHAr —O —SiR3)... 

Oxo-3-triethylsilyloxy-.3-trilluoro-methyl- ElOb,. 411 (1,4-Bcnzo-quinonc + F,C — SiR,)... 

Benzyloxy-meihyl)-8(or 7)-fluoro-7(oi 8)-hydroxy- ElObj. 144 (Oxirane + HF) 3-(l-Fluoro-4-mcihoxvcarbonyN butvl)-3-mcthoxy-7-trietIiyIsilyl-oxy-6-(3-triethylsilyloxy-l-octenyl)- ElOa, 268 (En +... 

Diphenyl-(1-phenyl-propyl)- E2, 147 Diphenyl-(2-phcnyl-vinyl)- E2, 66 Diphenyl-[2-(/ranv-2-phcnyl-vinyl)-phenyl)-aus Diphenyl-(2-phenyl-ethinyl)-phosphan und wasserhaltigem Ethanol E2, 48 Diphenyl-(phthalimino-methyl)- E2, 22 Diphenyl-piperidinomethyl- XII/1, 155 Diphenyl-1-propinyl- E2, 76 Diphenyl-tosyloxymethyl- El, 513 Diphenyl-(3-trialkylsik>xy-a]]yD- E2, 27 Diphenyl-trichlormethyl- XII/1, 151 F.2, 23 (Z)-Diphenyl-(3-triethylsilyloxy-allyl)- E2, 27 (Z)-Diphenyl-(3-triethylsilyloxy-2-butenyl)-aus Diphenyl-methoxy-phosphan und Chlor-triethyl-silan/3-Oxo-l-butcn E2, 27 Diphenyl-trifluoracctyl- E2, 8, 19, 42 Diphenyl-(2,2,2-lrifluor-ethyl)- E2, 16 Diphenyl-(l,l,3-trimethyl-2-butenyl)- E2, 71 Diphenyl-(trimethylsilyl-methyl)- E2, 22, 66 Diphcnyl-(l-trimethylsilyloxy-alkyl)- E2, 26 Diphenyl-triphenylmethyl-XlI/1,151 Diphenyl-(triphenylstannyl-methyl)-... 

Recently, Corey has rekindled interest in vinylstannanes as intermediates for alkenyl lithium reagents (79,80,81), and we (52,55) and others (53,56) have utilized this method to prepare various p-chain precursors (Scheme 17). We find hydrostanna-tion of terminal acetylenes to be a facile and high yield reaction, whereas iodovinylation is a capricious and tedious transformation. Thus, treatment of 3-triethylsilyloxy-l-octyne 91 with tributyl-stannane (TBS) in the presence of azobisisobutyronitrile (AIBN) gave stereospecifically an excellent yield of l-tributylstannyl-3-triethylsilyloxy-trans-l-octene (92), which when lithiated with butyllithium and treated with pentynylcopper provided the requisite lithio cuprate 93. The use of TBS to prepare homovinylic ethers such as 96 and 97 gave a 10 1 mixture of trans and cis isomers. 

Other Methyldiphenylsilylations. Methyldiphenylchlorosilane was used to form 6-silyluracils and uridines. The yields were better than those obtained with chlorotrimethylsilane (eq 9). The methyldiphenylsilylation of the lithium anion of 3-triethylsilyloxy-l,4-pentadiene occurs to place the methyldiphenylsilyl group on the 1-position, providing, after deprotection, the 8-methyldiphenylsilyl ketone (6) (eq 10). ... 

Table 1 Regioselective reactions of 3-Triethylsilyloxy-l,4-pentadiene with typical electrophiles...

General Discussion. 3-Triethylsilyloxy-l,4-pentadiene may be used to prepare the useful 3-triethylsilyloxypentadienyl anion via metalation with sec-butyUithium (eq 1). ... 

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