Bicyclization Involving Pseudo-Intramolecular Imination with Diamines

α-Nitro-δ-keto nitriles and α-nitro-δ-keto ester were readily converted to diazabicyclo compounds having vicinal functionality upon treatment with diamines. The keto nitrile attracts the diamine nearby to an acidic hydrogen to cause the pseudo-intramolecular imination which proceeds efficiently without any catalyst at room temperature

Reactive 2-Quinolones Dearomatized by Steric Repulsion between 1-Methyl and 8-Substited Groups

Usual 1-methyl-2-quinolone (MeQone) derivatives are not reactive because of aromatic property in the heterocyclic ring. On the other hand, 8-substituted MeQones have been proved to be highly reactive, which is caused by steric repulsion between the 1-methyl and the 8-substituted groups. When 1-methyl-3,6,8-trinitro-2-quinolone was treated with potassium (or trimethylsilyl) cyanide, cyanation proceeded at the 4-position regioselectively as a result of cine-substitution. This reaction is initiated with addition of cyanide species, and the cyanoquinolone is formed by the protonation of the resultant anionic intermediate followed by elimination of nitrous acid. The high reactivity was maintained even when one of the nitro groups on the benzene moiety was replaced by a methyl group, which afforded corresponding cine-substituted products upon treatment with potassium cyanide

One-step synthesis of differently bis-functionalized isoxazoles by cycloaddition of carbamoylnitrile oxide with β-keto esters

A new protocol for synthesizing different functionalized isoxazoles is provided. Carbamoylnitrile oxide generated from nitroisoxazolone underwent inverse electron-demand 1,3-dipolar cycloaddition with 1,3-dicarbonyl compounds in the presence of magnesium acetate that formed magnesium enolatein situ. Although electron-deficient trifluoroacetoacetate did not undergo this cycloaddition under the same conditions, conversion to sodium enolate furnish the corresponding bis-functionalized trifluoromethylisoxazole. The DFT calculations using B3LYP 6-31G+(d,p) also supported the aforementioned reactivity

One-Step Construction of 6-Aza-2-thiabicyclo[3.3.1]nona-3,7-diene Framework

The 6-aza-2-thiabicyclo[3.3.1]nona-3,7-diene framework was constructed upon treatment of dielectrophilic 3,5-dinitro-1-methyl-2-pyridone with S,C-dinucleophilic ethyl 3-thioxobutanoate, in which two moieties are connected by forming two bonds in the single manipulation

Rapid One-Pot Solvothermal Batch Synthesis of Porous Nanocrystal Assemblies Composed of Multiple Transition-Metal Elements

The ability of a rapid-heating solvothermal process to synthesize porous nanocrystal assemblies composed of the multiple transition metals was demonstrated. The rapid heating facilitated the quick formation of nascent nanocrystals to generate homogeneous mixed transition-metal oxides. Systematic studies of the synthesis of mixed-metal oxides under various experimental conditions indicated that the present simple method is suitable to develop a wide variety of binary and ternary transition-metal systems such as Co/Mn, Ni/Mn, and Co/Mn/Fe mixed-metal oxides. The products obtained from the rapid heating process were hierarchically assembled porous nanospheres composed of sub-10 nm nanocrystals, which had an extraordinarily high surface area and nano/mesopores. Electrochemical tests revealed the high catalytic ability of the porous nanocrystal assemblies in water oxidation