A new method has been developed for the preparation of pure (3-alkoxycarbonyl-2-oxopropyl)triphenyl-phosphonium 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. Bromo(silyl enol ether) esters react more efficiently with triphenylphosphine than the chloro(silyl enol ether) esters. tert-Butyldimethylsilyl enol ethers of alkyl 4-bromo-3-oxobutanoates and alkyl 4-chloro-3-oxobutanoates 7 also react with triphenylphosphine. Protection of isopropyl 4-bromo-3-oxobutanoate 7c as the enol acetate followed by subsequent reaction with triphenylphosphine gives (Z)-(2-acetoxy-3-isopropoxycarbonylbut-2-enyl)triphenylphosphonium bromide 17.

Item Type:	Refereed Article
Research Division:	Chemical Sciences
Research Group:	Organic chemistry
Research Field:	Organic chemical synthesis
Objective Division:	Expanding Knowledge
Objective Group:	Expanding knowledge
Objective Field:	Expanding knowledge in the chemical sciences
UTAS Author:	Moorhoff, CM (Dr Moorhoff)
ID Code:	12012
Year Published:	1997
Web of Science® Times Cited:	8
Deposited By:	Chemistry
Deposited On:	1997-08-01
Last Modified:	2011-08-15
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