[reaction: see text] A new class of thiourea catalysts have been developed which integrate saccharide and primary amine moieties into one small organic molecule. These simple catalysts are shown to be highly enantioselective for direct Michael addition of aromatic ketones to a range of nitroolefins (up to 98% ee).

A one-pot three-component cascade reaction proceeds by way of a Lewis acid-catalyzed Knoevenagel condensation/Nazarov cyclization/electrophilic fluorination sequence to afford fluorinated 1-indanone derivatives in moderate to good yields with high diastereoselectivities.

No abstract

Enantioselective syntheses O 0031Highly Enantioselective Michael Addition of Aromatic Ketones to Nitroolefins Promoted by Chiral Bifunctional Primary Amine-Thiourea Catalysts Based on Saccharides. -Thiourea bearing a chiral diamine and a saccharide unit represents a new type of organocatalyst for the asymmetric Michael addition of aryl ketones (I) to nitroolefins (II). A wide variety of substituents is tolerated on both substrates, and only low influence of electronic properties on reaction outcome is observed. -(LIU, K.; CUI, H.-F.; NIE, J.; DONG, K.-Y.; LI, X.-J.; MA*, J.-A.; Org. Lett. 9 (2007) 5, 923-925; Dep. Chem., Tianjin Univ., Tianjin 300072, Peop. Rep. China; Eng.) -Mischke 30-027

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Lewis Acid Catalyzed One-Pot Sequential Reaction for the Synthesis of α-Halogenated β-Keto Esters. -Halogenated 1-indanone derivatives are diastereoselectively prepared from β-ketoesters and aromatic aldehydes via sequential Knoevenagel condensation, Nazarov cyclization and halogenation. Several aromatic aldehydes with electron-withdrawing groups provide unexpected dichloro-β-ketoesters (VII). -(CUI, H.-F.; DONG, K.-Y.; NIE, J.; ZHENG, Y.; MA*, J.-A.; Tetrahedron Lett. 51