A quantitative approach to nucleophilic organocatalysis

• Herbert Mayr,
• Sami Lakhdar,
• Biplab Maji and
• Armin R. Ofial

Beilstein J. Org. Chem. 2012, 8, 1458–1478, doi:10.3762/bjoc.8.166

• °C, silyl ketene acetal 7b in dichloromethane with c(3a-CF3CO2) = (1.7–2.5) × 10−5 M, kryptopyrrole 12a in acetonitrile with c(3a-CF3CO2) = 5.0 × 10−5 M). Comparison of calculated and experimental rate constants of electrophilic aromatic substitutions with iminium ions [56]. Aza-Michael additions of

Synthesis of chiral sulfoximine-based thioureas and their application in asymmetric organocatalysis

• Marcus Frings,
• Isabelle Thomé and
• Carsten Bolm

Beilstein J. Org. Chem. 2012, 8, 1443–1451, doi:10.3762/bjoc.8.164

• organic transformations with hydrogen bond accepting substrates. Recently, we reported the enantioselective ring opening of cyclic meso-anhydrides and asymmetric Michael additions of 1,3-dicarbonyl compounds to nitroalkenes with thiourea-based organocatalysts [48][49]. Based on those studies and in the

Catalyst-free and solvent-free Michael addition of 1,3-dicarbonyl compounds to nitroalkenes by a grinding method

• Zong-Bo Xie,
• Na Wang,
• Ming-Yu Wu,
• Ting He,
• Zhang-Gao Le and
• Xiao-Qi Yu

Beilstein J. Org. Chem. 2012, 8, 534–538, doi:10.3762/bjoc.8.61

• environmentally hazardous residues and undesirable byproducts [25][26][27][28][29][30]. As one part of our continuing efforts toward the development of green synthesis methods for Michael additions of nitroalkenes, we have previously reported an enzymatic tandem reaction to form 5-hydroxyimino-4,5-dihydrofurans

Syntheses and applications of furanyl-functionalised 2,2’:6’,2’’-terpyridines

• Jérôme Husson and
• Michael Knorr

Beilstein J. Org. Chem. 2012, 8, 379–389, doi:10.3762/bjoc.8.41

• . Unfortunately, when applied to the synthesis of furanyl-substituted tpy 12, this method leads to irreproducible results [19]. Even turning to barium hydroxide as a base (which is known to favour Michael additions [20]) did not improve the course of the reaction in a substantial manner. Therefore, basic alumina

• [19][21] was tested, since it is known to be an efficient promoter of aldol condensations and Michael additions under solvent-free conditions [22][23]. Nevertheless, the treatment of furanyl-substituted aldehydes 1, 3 and 15 did not yield the targeted diketo-intermediates, but instead the chalcones 5

Amines as key building blocks in Pd-assisted multicomponent processes

• Didier Bouyssi,
• Nuno Monteiro and
• Geneviève Balme

Beilstein J. Org. Chem. 2011, 7, 1387–1406, doi:10.3762/bjoc.7.163

• transformations, including aza-Michael additions, hydroaminations of alkynes, Buchwald–Hartwig aminations, and allylic aminations, thereby allowing the creation of several covalent bonds in a single operation. Imine derivatives are also of high synthetic value as they may act either as electrophilic or