NaOH-catalyzed crossed Claisen condensation between ketene silyl acetals and methyl esters

We have developed a practical crossed Claisen condensation between ketene silyl acetals and methyl esters using catalytic NaOH to obtain alpha-monoalkylated beta-keto esters and inaccessible alpha,alpha-dialkylated beta-keto esters.     

A method for measuring specific activities of 14C-labelled compounds by gas chromatography-mass spectrometry-computer system

A method for measuring specific activities of 14C-labelled compounds by gas chromatography-mass spectrometry-computer system (GC-MS-CPU) was developed. This method was proved to provide practically precise and accurate specific activities of various 14C-labelled compounds with such merits as requirement of small amount of samples, being applicable to volatile compounds, and convenience. The C.V. percent obtained for tested compounds was within 3.9 and the reliable sensitivity should be over 37 MBq/mM (1 mCi/mM). This method was also useful for obtaining information on the labelling pattern and the synthetic procedures applied.     

Separation of drugs by high-performance liquid chromatography with porous polymer resins.

The separation of cold drugs and neuroleptics by high-performance liquid chromatogarphy with the porous polymer resin DVB-MCL-O (or 11-30-0), which is a styrene-divinylbenzene-methyl methacrylate copolymer substituted with hydroxymethyl groups, was studied. This copolymer was compared with the commercial porous polymers Hitachi gel 3011, 3011-0 and 3030. A very small theoretical plate height was obtained by using DVB-MCL-O and methanol-ammonia solution (99:1) as the stationary and mobile phases, respectively. This combination was found to be the most suitable for the rapid separation of condensed aromatic ring compounds.     

Carboncarbon bond formation by cross-coupling of enol phosphates with organoaluminium compounds catalyzed by palladium(O) complex

Trialkylaluminium-mediated alkylation of enol phosphates under the CO bond cleavage is performed stereospecifically in the presence of a catalytic amount of Pd(PPh₃)₄. Alkenylation and alkynylation are also described.     

Solid-state reaction of niobium with diamond carbon at high pressure and high temperature to form superconducting composite

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Iron-catalyzed synthesis of glycine derivatives via carbon-nitrogen bond cleavage using diazoacetate

Treatment of tertiary amines with diazoacetate in the presence of a catalytic amount of an iron salt, FeCl(3), in ethanol gave glycine derivatives. In this reaction, a carbon-nitrogen single bond of the amine was cleaved.     

Synthesis of functionalized pentacenes from isobenzofurans derived from C-H bond activation

The synthesis of unsymmetric functionalized pentacenes from 1,4-anthraquinones and functionalized isobenzofurans, which were prepared by transformation via C-H bond activation, was successfully accomplished. Examples of the synthesis of pentacenes with functional groups at the 5-position are still rare. These obtained functionalized pentacenes are highly soluble in hexane, toluene, and THF.