Domino reactions of 5-deoxy-5-iodo-d-xylo- and -l-arabinofuranose derivatives with organometallic reagents. A way towards polyfunctionalized building-blocks

Abstract: Domino reactions involving metal–halogen exchange, furanose ring-opening and nucleophilic addition from 3-O-benzyl-5-deoxy-5-iodo-1,2-O-isopropylidene-α-d-xylofuranose and the epimeric l-arabino derivative with various organometallic reagents are reported. In anhydrous conditions, with a large excess of organolithium or Grignard reagents, vicinal diols are obtained with good yields and a fair diastereoselectivity. Interestingly, with α-trimethylsilyl organolithium reagents, the fragmentation of the furanose ring to the substituted pent-4-enal is followed by a Peterson olefination giving dienic compounds in a four-step one-pot process. [Copyright &y& Elsevier]