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Synthesis of Substituted Tetrahydropyrans via Intermolecular Reactions of δ-Halocarbanions with Aldehydes. -Coupling of δ-bromocarbanions with non-enolizable aldehydes provides a simple, efficient, and general approach to trans-substituted tetrahydropyrans like (III). -(BARBASIEWICZ, M.; BRUD, A.; MAKOSZA*, M.; Synthesis 2007, 8, 1209-1213; Inst. Org. Chem., Pol. Acad. Sci., PL-01-224 Warsaw, Pol.; Eng.) -Jannicke 34-129

Sulfones Q 0600Reactions of Carbanions Derived from α-Substituted Methyl Tolyl Sulfones with Quinone Methides as Michael Acceptors. -Michael addition, rearrangement and vicarious nucleophilic substitution products are obtained depending on substrate structure and reaction conditions. -(GROSZEK*, G.; BLAZEJ, S.; BRUD, A.; SWIERCZYNSKI, D.; LEMEK, T.; Tetrahedron 62 (2006) 11, 2622-2630; Fac. Chem., Univ. Technol., PL-35-959 Rzeszow, Pol.; Eng.) -Nuesgen 25-102

Intramolecular substitution in δ-halocarbanions leading to cyclobutanes is a relatively slow process, thus they readily add to carbonyl groups; the thus-produced anionic adducts cyclize to tetrahydropyran derivatives. A simple mechanistic discussion, optimization of the reaction conditions, and scope of the reaction is presented