A method for producing methionine involves contacting 2-amino-4-(methylthio)butanenitrile with water in the presence of an oxide catalyst containing cerium. The 2-amino-4-(methylthio)butanenitrile may be 2-amino-4-(methylthio)butanenitrile, produced by contacting 2-hydroxy-4-(methylthio)butanenitrile with ammonia water or 2-amino-4-(methylthio)butanenitrile, produced by contacting 3-(methylthio)propionaldehyde with hydrocyanic acid and ammonia water.

The present invention relates to a process to prepare a benzimidazole derivative useful as a medicament, an intermediate for preparing the medicament, and a process to prepare the intermediate.

A polyether diol compound represented by the following formula (3):

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where R.sup.5, R.sup.6, R.sup.7 and R.sup.8, which may be the same as or different from each other, each represent a linear or branched alkyl group having 1 to 6 carbon atoms.

Synthesizing methanol from a synthesis gas and separating an unreacted gas from a reaction mixture obtained by passing through the synthesis step, the method including a synthesis loop having at least two synthesis steps and at least two separation steps; obtaining a first mixed gas by increasing through a circulator a pressure of a residual gas, obtained by removing a purge gas from the final unreacted gas separated from the final reaction mixture subsequent to the final synthesis step, and by mixing the residual gas with a fraction of a make-up gas; synthesizing methanol; separating a first unreacted gas from the first reaction mixture obtained in the synthesizing step; obtaining a second mixed gas by mixing the first unreacted gas and a fraction of the make-up gas; finally synthesizing methanol; and separating the final unreacted gas from the final reaction mixture obtained in the final synthesis step.

A crystal form of 2-(3,5-dimethyl-1H-pyrazol-1-yl)-5-methylphenol which is stable and has high purity for preservation, industrial manufacturing, and circulation, and process for providing the same by using a boron compound.

A hydrosilylation reaction catalyst prepared from: a catalyst precursor comprising a transition metal compound, excluding platinum, belonging to group 8-10 of the periodic table, e.g., iron acetate, cobalt acetate, nickel acetate, etc.; and a ligand comprising an isocyanide compound such as t-butyl isocyanide. The hydrosilylation reaction catalyst has excellent handling and storage properties. As a result of using this catalyst, a hydrosilylation reaction can be promoted under gentle conditions.

This invention provides a method capable of efficiently producing 2,3,3,3-tetrafluoropropene (HFO-1234yf) with a recycling step using substantially a single reaction step. A method for producing 2,3,3,3-tetrafluoropropene (HFO-1234yf), comprising a reaction step of reacting at least one chlorine-containing starting compound selected from the group consisting of chlorine-containing alkanes represented by formula (1): CX.sub.2YCHClCH.sub.2Z (wherein X, Y and Z independently represent H, F or Cl) and chlorine-containing alkenes represented by formula (2): CX.sub.2YCCl═CZ.sub.2 (wherein X, Y and Z independently represent H, F or Cl) with a fluorinating agent, wherein the molar ratio of the chlorine-containing starting compound represented by formula (1) or (2) newly supplied to the reactor inlet is less than 1.2 relative to 2-chloro-3,3,3-trifluoropropene (HCFO-1233xf) in components obtained from the reactor outlet.

Provided are a three-phase AC/DC converter disposed between a three-phase AC power supply and a light emitting diode group, the converter including a three-phase full bridge circuit in which pairs of switching elements are connected in parallel between DC buses for the three phases of the three-phase AC power supply; reactors connecting connection portions between the switching elements and corresponding phases of the three-phase AC power supply; a smoothing capacitor on the output side of the three-phase full bridge circuit; a DC voltage detection means; a power supply voltage phase detection means; and a pulse width modulation means for outputting pulse width modulation signals of the switching elements, wherein the pulse width modulation means outputs the pulse width modulation signals based on a power supply voltage phase and an output voltage between the DC buses.

The present invention relates to a method for producing a 3-methylcycloalkenone compound and a method for producing muscone. In the presence of a zirconium oxide catalyst, a diketone represented by the following general formula (1):

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wherein in formula (1), n represents 8, 9, 10, 11 or 12,
is subjected to a vapor-phase intramolecular condensation reaction, whereby a 3-methylcycloalkenone compound can be produced with high reaction efficiency. When a 3-methylcyclopentadecenone compound produced by this method is hydrogenated in a known manner, muscone can be produced efficiently.

A diphenylsulfone compound containing 4,4′-dihydroxydiphenylsulfone is produced in good yield in a short time and at a relatively low temperature. A diphenylsulfone compound represented by formula (2) below is produced by irradiating, with microwaves, a compound represented by formula (1) below and a sulfonating agent so that a dehydration condensation reaction is carried out.

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