Synthetic studies on ethyl α,β-unsaturated β-nitrocarboxylates (IV) through two routes are described. Ethyl α-hydroxy-β-nitrocarboxylates (II) obtained by the reactions of ethyl α,β-unsaturated carboxylates with fuming nitric acid or by those of nitroparafins with ethyl glyoxylate, were treated with acetic anhydride to afford ethyl α,-acetoxy-β-nitrocarboxylates (III), which were subsequently converted
Ethyl cinnamate was allowed to react with nitrogen monoxide (NO) by photoirradiation in the presence of metallosalen complexes (4), oxygen, and axial ligands for 4 to yield furoxan derivatives (6). Oxygen and axial ligands are indispensable for this reaction. Photoirradiation enhanced the yield of 6. Lowering the reaction temperature increased the yield of 6 up to 55% (at −5 °C).
Catalytic Asymmetric Friedel–Crafts/Protonation of Nitroalkenes and <i>N</i>-Heteroaromatics
作者:Takayoshi Arai、Atsuko Awata、Makiko Wasai、Naota Yokoyama、Hyuma Masu
DOI:10.1021/jo200546a
日期:2011.7.1
The catalyticasymmetric Friedel–Crafts/protonation of indoles and pyrroles with α-substituted nitroalkenes to give the corresponding adducts in a highly anti-selective manner was achieved by an imidazoline–aminophenol (L2)–Cu complex. The anti-adducts could be successfully transformed to biochemically important α-substituted β-heteroarylalkylamines.
Solvent-Free, <i>anti</i>-Michael
Addition of Active Methylene Derivatives to β-Nitroacrylates:
Eco-Friendly, Chemoselective Synthesis of Polyfunctionalized Nitroalkanes
The chemoselective, anti-Michael addition of active methylene derivatives to β-nitroacrylates can be easily performed at room temperature, under solvent-free conditions, using a catalytic amount of potassium carbonate as heterogeneous catalyst.
Catalyst free, regioselective one-pot three-component synthesis of thiazol-2-imine derivatives in ionic liquid
作者:G. Santosh Kumar、S. Pushpa Ragini、H.M. Meshram
DOI:10.1016/j.tetlet.2013.08.056
日期:2013.11
A one-potthree-component approach for the synthesis of thiazol-2-imines has been described by the reaction of amine, phenyl isothiocyanate and β-nitroacrylate in [Hbim]BF4 ionicliquid. The method is applicable for aromatic, benzylic, aliphatic and cyclic amines. Reusable reaction media, regioselectivity, mild reaction condition, catalyst free and high yield of products are the salient features of