Portal de Periódicos da CAPES

Efficient O ‐ and N ‐( β ‐fluoroethylation)s with NCA [ 18 F] β ‐fluoroethyl tosylate under microwave‐enhanced conditions

2004; Wiley; Volume: 47; Issue: 5 Linguagem: Inglês

10.1002/jlcr.818

1099-1344

Shuiyu Lu, Frederick T. Chin, Julie A. McCarron, Victor W. Pike,

Chemical Synthesis and Analysis

Abstract Reactions of no‐carrier‐added (NCA) [ 18 F] β ‐fluoroethyl tosylate with amine, phenol or carboxylic acid to form the corresponding [ 18 F] N ‐( β ‐fluoroethyl)amine, [ 18 F] β ‐fluoroethyl ether or [ 18 F] β ‐fluoroethyl ester, were found to be rapid (2–10 min) and efficient (51–89% conversion) under microwave‐enhanced conditions. These conditions allow reactants to be heated rapidly to 150°C in a low boiling point solvent, such as acetonitrile, and avoid the need to use high boiling point solvents, such as DMSO and DMF, to promote reaction. The microwave‐enhanced reactions gave about 20% greater radiochemical yields than thermal reactions performed at similar temperatures and over similar reaction times. With a bi‐functional molecule, such as DL‐pipecolinic acid, [ 18 F] β ‐fluoroethyl tosylate reacts exclusively with the amino group. Copyright © 2004 John Wiley & Sons, Ltd.