D.A. Evans The Shapiro Reaction-2 Chem 206 Trapping of the intermediate alkenyllithium Ts R -STBS N CO2H =12:1 Me2NCHO 81% SiMe3 "Me3SiCI >20:1(E):2) Applications Myers, J. Am. Chem. Soc. 1990, 112, 8208 c6H13 NHTris 1. TSNHNH2, TSOH TMEDA/hexane 2. nBuLi TMEDa o 82% Bloom Tet lett 1984. 25. 4901 van Tamelen J. Am. chem. soc. 1983. 105. 142 Carbonyl Transposition 1. 2.1 equiv. nBuLi NNHTris BuLi TMEDATHF 2 eq HgCl2 2. Messe 3. 1 3quiv BuLi SMe Nakai Chem Lett. 1980. 1099 75% Shapiro alternatives Me COmE COmE COmE 2.7 eq LDA 0°cTHF styrene OH Me (Juvabione)Evans J. Am. Chem. Soc. 1980, 102, 774 loroxanthin Bautikofer Helv Chim. Acta. 1983. 66. 1148N Cl NHTris C6H13 R’ OH R SiMe3 C6H13 R’ R O Me3SiCl RCH2Br Li Cl Br+ C6H13 Li CH2R C6H13 C6H13 Br CO2 Me2NCHO C6H13 CO2H CHO C6H13 N N Me Ph H TBS Ts O O Me Me H H O O O O O O N N(TBS)Ts Li H Me Et N H H N Ts TBS Ph C4H9 Me Me Me Me NNHTris Me HO Me Me Me HO Me Me Me Me Me Me OH Me OH HO Me Me Me Me Me Me Me Me Me NNHTs Me SMe Me O Me OMe O CO2Me H H2N N Ph H CO2Me N Me OMe N Ph H CO2Me Me OMe BuLi -N2 RCHO H H Me Me O O N N Me Ph C4H9 H H O O O O O Et Me H HO Li Me Me Me C4H9 Ph Me Myers, J. Am. Chem. Soc. 1990, 112, 8208 >20:1 (E):(Z) 81 % + 2. HOAc (E):(Z) = 12:1 -"TsTBS" 1. nBuLi Aphidicolin van Tamelen J. Am. Chem. Soc. 1983, 105, 142. 82 % 2. nBuLi, TMEDA 1. TsNHNH2 , TsOH Applications D. A. Evans The Shapiro Reaction-2 Chem 206 Trapping of the intermediate alkenyllithium TMEDA/hexane 75 % loroxanthin Baütikofer Helv. Chim. Acta. 1983, 66, 1148 BusLi TMEDA/hexane -78°C 0°C 82 % Bloom Tet Lett. 1984, 25, 4901 Carbonyl Transposition 1. 2.1 equiv. nBuLi 2. MeSSMe TMEDA/THF 2 eq. HgCl2 82 % Nakai Chem. Lett. 1980, 1099 Shapiro alternatives 2.7 eq. LDA 0°C THF - styrene (Juvabione) Evans J. Am. Chem. Soc. 1980, 102, 774 3. 1 3quiv BuLi warm