title: Epi-cinchona based thiourea organocatalyst family as an efficient asymmetric Michael addition promoter: enantioselective conjugate addition of nitroalkanes to chalcones and alpha,beta-unsaturated N-acylpyrroles.
abstract: A small set of easily available epi-cinchona based thiourea organocatalysts have been synthesized and tested in enantioselective Michael addition of nitroalkanes to chalcones. These bifunctional catalyst systems promoted the conjugate additions with high enantioselectivities and chemical yields. The extension of this methodology was further explored to encompass alpha,beta-unsaturated N-acylpyrroles, as a chalcone mimic. Functionally, the N-acylpyrrole moiety in the adduct acts as an ester surrogate; therefore, it can easily be transformed to various valuable and biologically relevant compounds. This approach allowed the concise stereoselective synthesis of (R)-rolipram.
authors: Institute of Biomolecular Chemistry, Chemical Research Center of Hungarian Academy of Sciences, Budapest, Hungary.
authors: Benedek
authors: B
authors: Vakulya
authors: Szilárd
authors: S
authors: Varga
authors: Tibor
authors: T
authors: Soós
mesh_terms: D000143:Acids / Q000737:chemistry; D000215:Acylation; D000473:Alkanes / Q000737:chemistry*; D000588:Amines / Q000737:chemistry; D002384:Catalysis; D002599:Chalcone / Q000138:chemical synthesis* / Q000737:chemistry; D002929:Cinchona / Q000737:chemistry*; D008697:Methane / Q000737:chemistry; D015394:Molecular Structure; D009574:Nitro Compounds / Q000737:chemistry*; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry; D020889:Rolipram / Q000138:chemical synthesis / Q000737:chemistry; D013237:Stereoisomerism; D013890:Thiourea / Q000737:chemistry*
chemical_list: D000143:Acids; D000473:Alkanes; D000588:Amines; D009574:Nitro Compounds; D011758:Pyrroles; D002599:Chalcone; D013890:Thiourea; D020889:Rolipram; D008697:Methane