The synthesis of 2,5-dihydrofurans from α-allenic alcohols

✍ Scribed by Pierre L. Beaulieu; Veronique M. Morisset; Dennis G. Garratt

• Publisher: Elsevier Science
• Year: 1980
• Tongue: French
• Weight: 229 KB
• Volume: 21
• Category: Article
• ISSN: 0040-4039
• DOI: 10.1016/s0040-4039(00)71393-1

✦ Synopsis

a-Allenic alcohols react rapidly with PhSeCl to produce derivatives of 3-phenylseleno-2,5-dihydrofuran in high yields. The synthesis of heterocycles via the electrophilically-induced cyclization of unsaturated acids,' alcohols, 2 and phenols with areneselenenyl halides or derivatives thereof4 has recently received a great deal of attention by the groups of Clive and Nicolaou. In particular, Clive and coworkers have demonstrated the utility of the reaction of y,6 unsaturated alcohols with benzeneselenenyl chloride, 1, to produce ring-fused tetrahydrofurfns 2a . While electrophilicallya induced ring closures of this type have been known for many years', the advantage of such a closure under these conditions arises from the facile nature of the process and the existence the phenylseleno moiety as a potential synthon for further synthetic transformations 637 . The availability of diastereoisomeric a-allenic alcohols', plus the known propensity for selenenyl halides to react with carbon-carbon double bonds in an anti stereospecific manner', suggested to us the possibility of a facile synthetic route to configurationally well-defined of 2,5dihydrofurans. It must be noted, however, that conceptually there exist two distinct modes of cyclization if the phenylseleno moiety forms a new bond with the central carbon of the allenic system (equation Cl]), which seems likely 10 .