The reactivity of α,β-unsaturated sulfonates and aromatic thiols in an organocatalyzed sulfa-Michael addition was explored. Bifunctional chiral thiourea catalysts were found to promote the reaction, and the corresponding Michael adducts were afforded in moderate to good yields (24-92 %)

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Enantioselective syntheses O 0031Enantioselective Alkylation of Reissert Compounds in Phase Transfer Catalyzed Reactions. -The first enantioselective alkylation of isoquinoline Reissert compounds (I) under phase-transfer reaction conditions uses chiral quaternary ammonium salts derived from Cinchona alkaloids as catalysts. Enantioselectivities up to 65% e.e. are achieved. -(BROZDA, D.; HOFFMAN, K.; ROZWADOWSKA*, M. D.; Heterocycles 67 (2006) 1, 119-122; Fac. Chem., Adam Mickiewicz Univ., PL-60-780 Poznan, Pol.; Eng.) -R. Langenstrassen 21-034

Sulfonic acids and esters Q 0550Organocatalytic Asymmetric Sulfa-Michael Additions to α,β-Unsaturated Sulfonates. -A quinine-derived thiourea promotes the reaction to afford β-sulfur-substituted sulfonic acid derivatives. -(ENDERS*, D.; HOFFMAN, K.; Eur.