D. A. Evans The peterson olefination reaction Chem 206 a Simple Examples: Taken from Organic Rxns review Miyakolide(+1-1 Ripin, Halstead, and Campos Me3 Si-CH2Mge→ cs199121,68166826 Nah orison This reagent is better that H2C=PPh3 for hindered ketones olefin geometry challenge Boeckman, Tet. Lett 1973, 3437 0 OMe TMS LNOM OEt >95% Nozaki JACS 1974. 96. 1620 OPMB OPMB CO, Me B-BuLi ba olvent E: Z >90% LDA THF 73:27 NaHMDS THF 18:82 Chan. Tet. Lett 1978. 2383 LDA PhMe 66: 33 n-Hexyl Chan, Chem. Commun 1982, 969 Hudrlik, JACS 1981, 103, 6251D. A. Evans The Peterson Olefination Reaction Chem 206 Boeckman, Tet. Lett 1973, 3437 ■ Simple Examples: Taken from Organic Rxns review NaH orTsOH This reagent is better that H2C=PPh3 for hindered ketones >90% O Me3Si CH2MgBr OH SiMe3 CH2 Me O Me H H Me H2C Me Chan, Tet. Lett 1978, 2383 Nozaki, JACS 1974, 96, 1620 >95% >90% O Me3Si OEt O O OEt Me3Si SiMe3 OH O O O O Me Me Me H O Me OH Me OH OH OMe OH Me O O Miyakolide (+)-1 H H O OPMB O OMe Me O Xp 1 9 O OPMB OMe Me O Xp 1 9 CO2Me entry base solvent E : Z 1 2 3 4 LDA NaHMDS 73 : 27 18 : 82 66 : 33 66 : 33 LDA LDA TMS OMe O Conditions –78 °C 19-E with Ripin, Halstead, and Campos JACS 1999, 121, 6816-6826. Miyakolide presents an interesting olefin geometry challenge Chan, Chem. Commun 1982, 969 R OH SiMe3 Me3Si B O O Me Me Me R Me R Hudrlik, JACS 1981, 103, 6251 Me3Si H n-Hexyl O OH CMe3 OLi n-Hexyl Me3Si CMe3 O O CMe3 n-Hexyl OH CMe3 n-Hexyl OH n-Hexyl Me3Si CMe3 OH LiN(TMS)2 t-BuLi MgBr2 SOCl2 THF Et2O THF PhMe H + KH RCHO BF3 •OEt2 KH