Nagatoshi Nishiwaki

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Unnatural 1-methyl-2-quinolone derivatives were synthesized by regioselective C-C bond formation. When 1-methyl-3,6,8-trinitro-2-quinolone (TNQ) was treated with enamines, nucleophilic addition readily occurred at the 4-position, and succeeding hydrolysis of enamine moiety followed by elimination of nitrous acid furnished(More)
The acyl group of an alpha-aryl-beta-keto ester was readily transferred to N-, O-, and S-nucleophiles. The transacylation from arylated diethyl 3-oxoglutarate to amines led to unsymmetrical malonic acid amide esters in high yields. The present reaction proceeded under mild conditions without formation of detectable byproducts. Only simple experimental(More)
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.
Nickel complexes of a series of β-diketiminate ligands ((R)L(-), deprotonated form of 2-substituted N-[3-(phenylamino)allylidene]aniline derivatives (R)LH, R = Me, H, Br, CN, and NO2) have been synthesized and structurally characterized. One-electron oxidation of the neutral complexes [Ni(II)((R)L(-))2] by AgSbF6 or [Ru(III)(bpy)3](PF6)3 (bpy =(More)
An improved method, which is highly reproducible, was developed for the enantioseparation of racemic O-ethyl phenylphosphonothioic acid (1a) with brucine by introducing seeding to a supersaturated solution of the diastereomeric salt mixture. The present method gave both diastereomeric salts in high yields with a diastereomeric ratio of >99.5:0.5 upon(More)
A commercially purchased acetoacetamide was found to dimerize during storage for several months to afford 4,6-dimethyl-2-pyridone-5-carboxamide. We successfully achieved the quantitative dimerization of acetoacetamide by using an acid catalyst. It was also found that the pyridone formed served as a self-catalyst of the dimerization.
A novel use of GaAs, namely, as a scaffold for a heterogeneous palladium catalyst, is proposed. Hydroxy groups on the GaAs surface play important roles. During the adsorption of Pd(OAc)(2) on the GaAs surface, the hydroxy groups attract Pd(ii) species by anion exchange. A subsequent redox reaction proceeds to generate Pd(0) nanoparticles, which are(More)
3,5-Dinitro-1,4-dihydropyridines (DNDHPs) are readily constructed by the acid-promoted self-condensation of β-formyl-β-nitroenamines. In the DNDHPs, one molecule of the nitroenamine serves as a C3N1 building block and the other serves as a C2 block. This synthetic method does not require any special reagents and conditions. When the reaction is conducted in(More)
The 1-methyl-2-quinolone (MeQone) framework is often found in alkaloids and recently attention was drawn to unnatural MeQone derivatives with the aim of finding new biologically active compounds, however, low reactivity of the MeQone framework prevents the syntheses of versatile derivatives. A nitro group is one of the useful activating groups for this(More)