Gold(I)-catalyzed alkoxyhalogenation of beta-hydroxy-alpha,alpha-difluoroynones.

(Chemical Equation Presented) Gold standard: AuCl was found to be the only suitable catalyst for the 6-endo-dig ring closure of hydroxylated difluorinated ynones (see scheme), a class of substrates that displays low reactivity owing to the presence of the gem-difluoro group. For the first time, a gold catalyst is used in combination with an electrophilic fluorinating reagent. © 2008 Wiley-VCH Verlag GmbH and Co. KGaA