Abstract: To provide an electrolytic solution that suppresses increase in the OH? ion concentration even in the case of electrochemical changes and thereby reduces deterioration or corrosion of resin, rubber, or metal to improve the reliability of an electrochemical device, an electrolyte used in the electrolytic solution, and an electrochemical device comprising the electrolytic solution. The electrolyte, for example, comprises a compound having a cation unit represented by the following formula and an electrolyte (a quaternary ammonium salt or the like). (In the formula, R1, R2, R3, and R4 are the same or different and each represent an alkyl group or an alkoxyalkyl group; R1 and R2 may together form a ring such as a pyrrolidine ring and a piperidine ring; and R3 and R4 may together form a ring such as a pyrrolidine ring and a piperidine ring.

Abstract: The present invention provides a nonaqueous electrolytic solution that provides an electric double layer capacitor having excellent durability. The nonaqueous electrolytic solution of the present invention is a nonaqueous electrolytic solution for electric double layer capacitors prepared by dissolving a quaternary ammonium salt as an electrolyte in a nonaqueous solvent, and the nonaqueous electrolytic solution has an alkali metal cation concentration of 0.1 to 30 ppm.

Abstract: To provide an electrolytic solution that suppresses increase in the OH? ion concentration even in the case of electrochemical changes and thereby reduces deterioration or corrosion of resin, rubber, or metal to improve the reliability of an electrochemical device, an electrolyte used in the electrolytic solution, and an electrochemical device comprising the electrolytic solution. The electrolyte, for example, comprises a compound having a cation unit represented by the following formula and an electrolyte (a quaternary ammonium salt or the like). (In the formula, R1, R2, R3, and R4 are the same or different and each represent an alkyl group or an alkoxyalkyl group; R1 and R2 may together form a ring such as a pyrrolidine ring and a piperidine ring; and R3 and R4 may together form a ring such as a pyrrolidine ring and a piperidine ring.

Abstract: Provided is a nonaqueous electrolytic solution that provides an electric double layer capacitor having excellent durability. The nonaqueous electrolytic solution is prepared by dissolving a quaternary ammonium salt as an electrolyte in a nonaqueous solvent, and the nonaqueous electrolytic solution comprises a diethylpyrrolidinium salt and/or a 1-ethyl-1,3-dimethylpyrrolidinium salt.

Abstract: The present invention provides a nonaqueous electrolytic solution that provides an electric double layer capacitor having excellent durability. The nonaqueous electrolytic solution of the present invention is a nonaqueous electrolytic solution for electric double layer capacitors prepared by dissolving a quaternary ammonium salt as an electrolyte in a nonaqueous solvent, and the nonaqueous electrolytic solution has an alkali metal cation concentration of 0.1 to 30 ppm.

Abstract: Provided is a nonaqueous electrolytic solution that provides an electric double layer capacitor having excellent durability. The nonaqueous electrolytic solution is prepared by dissolving a quaternary ammonium salt as an electrolyte in a nonaqueous solvent, and the nonaqueous electrolytic solution comprises a diethylpyrrolidinium salt and/or a 1-ethyl-1,3-dimethylpyrrolidinium salt.

Abstract: An object of the invention is to provide an industrially advantageous process capable of remarkably suppressing the generation of an undesirable by-product cepham compound to thereby efficiently produce a desired 2?-methyl-2?-[(1,2,3-triazol-1-yl)methyl]penam-3?-carboxylic acid ester. In the present invention, a diphenylmethyl 2?-bromomethyl-2?-methylpenam-3?-carboxylate (BMPB) is reacted with 1,2,3-triazole in a halogenated hydrocarbon solvent at ?5° C. or lower. The reaction in a halogenated hydrocarbon solvent at ?5° C. or less can remarkably suppress the generation of an undesirable by-product cepham compound, so that the desired diphenylmethyl 2?-methyl-2?-[(1,2,3-triazol-1-yl)methyl]penam-3?-carboxylate (TMPB) can be efficiently produced.

Abstract: The present invention provides novel 2?-methyl-2?-[(1,2,3-triazol-1-yl)methyl]penam-3?-carboxylic acid benzhydryl ester (TMPB)-acetone crystals for use in the production of 2?-methyl-2?-[(1,2,3-triazol-1-yl)methyl]penam-3?-carboxylic acid 1,1-dioxide benzhydryl ester (TAZB); a process for producing the TMPB-acetone crystals comprising the steps of (A) concentrating a TMPB-containing organic solvent solution, (B) dissolving the resulting concentrate in acetone, and (C) precipitating TMPB-acetone crystals from the acetone solution thus obtained; and a process for producing TAZB comprising the step of reacting the TMPB-acetone crystals with an oxidizing agent.

Abstract: A process for preparing a penicillanic acid compound of the formula (2) comprising reacting a halogenated penicillanic acid compound of the formula (1), (a) in the presence of a metal bismuth or bismuth compound, (b) with a metal having a lower standard oxidation-reduction potential than bismuth to obtain the compound (2) (X and Y are a hydrogen atom or halogen atom, provided that X and Y are not hydrogen atoms at the same time, n is an integer of 0 to 2, R is carboxylic acid protecting group) (n and R are same as above).

Abstract: An object of the invention is to provide an industrially advantageous process capable of remarkably suppressing the generation of an undesirable by-product cepham compound to thereby efficiently produce a desired 2?-methyl-2?-[(1,2,3-triazol-1-yl)methyl]penam-3?-carboxylic acid ester. In the present invention, a diphenylmethyl 2?-bromomethyl-2?-methylpenam-3?-carboxylate (BMPB) is reacted with 1,2,3-triazole in a halogenated hydrocarbon solvent at ?5° C. or lower. The reaction in a halogenated hydrocarbon solvent at ?5° C. or less can remarkably suppress the generation of an undesirable by-product cepham compound, so that the desired diphenylmethyl 2?-methyl-2?-[(1,2,3-triazol-1-yl)methyl]penam-3?-carboxylate (TMPB) can be efficiently produced.

Abstract: The present invention provides novel 2?-methyl-2?-[(1,2,3-triazol-1-yl)methyl]penam-3?-carboxylic acid benzhydryl ester (TMPB)-acetone crystals for use in the production of 2?-methyl-2?-[(1,2,3-triazol-1-yl)methyl]penam-3?-carboxylic acid 1,1-dioxide benzhydryl ester (TAZB); a process for producing the TMPB-acetone crystals comprising the steps of (A) concentrating a TMPB-containing organic solvent solution, (B) dissolving the resulting concentrate in acetone, and (C) precipitating TMPB-acetone crystals from the acetone solution thus obtained; and a process for producing TAZB comprising the step of reacting the TMPB-acetone crystals with an oxidizing agent.

Abstract: A process for preparing a penicillanic acid compound of the formula (2) comprising reacting a halogenated penicillanic acid compound of the formula (1), (a) in the presence of a metal bismuth or bismuth compound, (b) with a metal having a lower standard oxidation-reduction potential than bismuth to obtain the compound (2) (X and Y are a hydrogen atom or halogen atom, provided that X and Y are not hydrogen atoms at the same time, n is an integer of 0 to 2, R is carboxylic acid protecting group) (n and R are same as above).

Abstract: The present invention is directed to a process for preparing an exo-methylenepenam compound wherein a cephem compound is reduced with a metal having a standard oxidation-reduction potential of up to −0.3 (V/SCE) in an amount of at least one mole per mole of the cephem compound and with a metal compound having a higher standard oxidation reduction potential than the metal and in an amount of 0.

Abstract: A process for preparing a 2-isocephem derivative characterized in that a thioacetic acid derivative which itself is basic or a mixture of a base and a thioacetic acid derivative is caused to act on a 2-azetidinyl-3,4-dihalogeno-2-butenoic acid compound represented by the general formula (1) in a water-containing organic solvent to obtain a 3-halomethyl-2-isocephem derivative represented by the general formula (2), and a process for preparing a 2-oxaisocephem derivative characterized in that a base is caused to act on a 2-azetidinyl-3,4-dihalogeno-2-butenoic acid compound represented by the general formula (1) in a water-containing organic solvent to obtain a 3-halomethyl-2-oxaisocephem derivative represented by the general formula (3) ##STR1## wherein R.sup.1 is a hydrogen atom, amino or protected amino, R.sup.2 is a hydrogen atom or lower alkoxyl, R.sup.1 and R.sup.2, when taken together, form a cyclic amino protecting group, R.sup.

Abstract: A process for preparing a 2-isocephem derivative characterized in that a thioacetic acid derivative which itself is basic or a mixture of a base and a thioacetic acid derivative is caused to act on a 2-azetidinyl-3,4-dihalogeno-2-butenoic acid compound represented by the general formula (1) in a water-containing organic solvent to obtain a 3-halomethyl-2-isocephem derivative represented by the general formula (2), and a process for preparing a 2-oxaisocephem derivative characterized in that a base is caused to act on a 2-azetidinyl-3,4-dihalogeno-2-butenoic acid compound represented by the general formula (1) in a water-containing organic solvent to obtain a 3-halomethyl-2-oxaisocephem derivative represented by the general formula (3) ##STR1## wherein R.sup.1 is a hydrogen atom, amino or protected amino, R.sup.2 is a hydrogen atom or lower alkoxyl, R.sup.1 and R.sup.2, when taken together, form a cyclic amino protecting group, R.sup.