Abstract5‐endo‐dig cyclisations of 3‐alkyne‐1,2‐diols using iodine as the electrophile proceed smoothly to deliver excellent yields of the corresponding β‐iodofurans. The necessary precursors are available from a number of different approaches, notably regioselective bis‐hydroxylation of conjugated enynes and the addition of acetylides to α‐hydroxy carbonyl groups. The initial iodofurans can be homologated using a number of strategies, ranging from various transition metal‐catalysed couplings to halogen–metal exchange and subsequent coupling with an electrophile. Hence, this method overall represents a flexible, relatively brief and very efficient approach to a variety of highly substituted furans. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)

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Practical Alternatives for the Synthesis of β-Iodofurans by 5-endo-Dig Cyclizations of 3-Alkyne-1,2-diols.-3-Alkyne-1,2-diols (I), readily available from α-hydroxyketones or esters and acetylides, undergo iodocyclization by a 5-endo-dig pathway yielding highly functionalized furans after dehydration. -(EL-TAEB, GAMILA M. M.; EVANS, ANN B.; JONES, SIMON; KNIGHT, DAVID W.; Tetrahedron Lett. 42 (2001) 34, 5945-5948; Dep. Chem., Cardiff Univ., Cardiff CF1 3TB, UK; EN)

2008Furan derivatives R 0060 Expedient Syntheses of β-Iodofurans by 5-endo-dig Cyclizations. -A general approach to the title compounds is developed using I 2 as the electrophile. The iodine substituent allows further functionalization to give highly substituted furan systems.Substrates bearing a terminal alkyne moiety [cf. (Vc)] do not react. -(BEW, S. P.; EL-TAEB, G. M. M.; JONES, S.; KNIGHT*, D. W.; TAN, W.-F.; Eur.