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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]

Abstract: A series of highly fluorinated compounds bearing two or four perfluoroalkyl (R F ) chains, with a flexible or rigid core have been synthesized. Radical additions, nucleophilic addition or condensation reactions were implemented for these synthesis, using perfluoroalkylated iodides and alcohols and various type of substrates: bis(allylic) derivatives, epichlorhydrin, diacid derivatives. All compounds contain an unsaturated moiety (vinyl, allyl or internal double bond) to be grafted on silicone materials by a catalyzed hydrosilylation reaction. [Copyright &y& Elsevier]

Abstract: A series of sulfonium salts derived from 1,5-dithiopent-1-enopyranosides was prepared in a three-step sequence from protected d- and l-erythrofuranoses. The key step is the nucleophilic displacement of a leaving group by a sulfur atom of carbohydrate-derived ketene dithioacetals. Such compounds were assayed for their properties as glycosidase inhibitors. [Copyright &y& Elsevier]

A highly diastereoselective nucleophilic mono(trifluoromethylation) of a tartaric acid-based diketone, using trifluoromethyl(trimethyl)silane, afforded the corresponding γ-keto trifluoromethylcarbinol. The scope and limitation of this reaction was studied. The acidic removal of the acetonide moiety protecting the two hydroxyl groups of the adducts was unsuccessful. Bis(O-methylation) of the aromatic derivatives under basic conditions, followed by acidic hydrolysis and oxidative cleavage, led to two different enantiopure products: an α-aryl-α-methoxy-α-trifluoromethyl ethanal and an α-aryl-α-methoxycarboxylic acid. The overall process is eventually an interesting way to convert one natural chiral raw material into two functionalized enantiopure building blocks including a trifluoromethyl one. [ABSTRACT FROM AUTHOR]