title: An improved method for the protection of carboxylic acids as 1,1-dimethylallyl esters.
abstract: 1,1-Dimethylallyl (DMA) esters of various N-protected amino acids have been synthesized using prenyldimethylsulfonium tetrafluroborate, a reagent that can be readily made and stored, in conjunction with catalytic CuBr. These reactions were complete within several hours and afforded DMA esters in high yields. As has been previously shown in our group, DMA esters represent a palladium-labile proctecting group for carboxylic acids that resists nucleophilic attack as a tert-butyl ester would.
authors.affiliation: Department of Chemistry and Cancer Center, Purdue University, West Lafayette, Indiana 47907-2084, USA.
authors.forename: Minoo
authors.initials: M
authors.lastname: Sedighi
authors.forename: Selçuk
authors.initials: S
authors.lastname: Calimsiz
authors.forename: Mark A
authors.initials: MA
authors.lastname: Lipton
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry*; D004952:Esters; D009682:Magnetic Resonance Spectroscopy; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D002264:Carboxylic Acids; D004952:Esters