e.g. Filippa Pettersson or Cancer Res. 75(6) , 1102-12, (2015) or 10.1002/anie.201600521
Journal of the Chemical Society, Perkin Transactions 1
Silyl enol ethers as new protecting groups for alkyl 4-halo-3-oxobutanoates; the preparation of pure (3-alkoxycarbonyl-2-oxopropyl) triphenylphosphonium salts
CM Moorhoff
Index: Moorhoff, Cornelis M. Journal of the Chemical Society - Perkin Transactions 1, 1997 , # 13 p. 1987 - 1995
A new method has been developed for the preparation of pure (3-alkoxycarbonyl-2-oxopropyl )triphenylphosphonium salts 8. Alkyl 4-bromo-3-oxobutanoates and alkyl 4-chloro-3-oxobutanoates 7 are protected as the trimethylsilyl enol ethers prior to treatment of the resulting bromo(trimethylsilyl enol ether) esters 20c and 21c with triphenylphosphine in toluene and then addition of a little water to give pure (3-isopropoxycarbonyl-2-oxopropyl)triphenylphosphonium bromide 8c. ...