Substituted vinyl ethers constitute some of the important substructures of bioactive compounds and a synthetically useful class of alkene functionalities because they are more electron-rich as compared with other alkenes. Vinyl ethers have been widely utilized in a large number of organic reactions such as Diels-Alder cycloaddition, Claisen reorganization, Nazarov cyclization8 and aldehyde homologation9 and applied to the syntheses of natural products, polymers and surfactants. The majority of the preparative approaches to substituted vinyl ethers are based on various types of olefinations of the carbonyl precursors, for example, Wittig,9 Horner-Wadsworth-Emmons13 and Julia-Kocienski reactions.14 As part of our efforts in the field of medicinal chemistry, we have intensively investigated olefination methods for the preparation of unexplored 2-naphthylmethyl vinyl ethers from benzaldehydes. Recently, Berthelette and co-workers reported the highly remarkable Julia olefination of a-alkoxy heteroaryl sulfones, which successfully provided benzyl, 4-chlorophenyl, and 2-methoxyefhyl vinyl ethers under strongly basic conditions (Scheme l).14 Considering the synthetic feasibility, this olefination would be applicable to the generation of uniquely challenging 2-naphthylmethyl vinyl ethers. Herein, we describe our efforts toward the expeditious synthesis of a new Julia-Kocienski reagent 1 and initial studies on its application to the facile preparation of some 2-naphthylmethyl vinyl ethers.
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