Metal-free oxidative fluorination of phenols with [18F]fluoride.

The radiochemical synthesis of [18F]4-fluorophenols is based on phenol umpolung under oxidative conditions and direct nucleophilic fluorination with [18F]fluoride (see scheme, TBAF=tetra-n-butylammonium fluoride, TFA=trifluoroacetic acid). Readily available O-unprotected 4-tert-butyl phenols are used as precursors in this one-pot protocol. The reaction is completed in less than 30 minutes at room temperature and can be performed using standard or microfluidic technology. Copyright © 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim