Claims
- 1. A process for preparing an exo-methylenepenam compound of formula (5) wherein R1 is selected from the group consisting of hydrogen, amino and protected amino; R2 is selected from the group consisting of hydrogen, halogen, C1-4 alkoxy, formyl, acetyl, propionyl, butyryl, isobutyryl and C1-4 alkyl which is substituted by hydroxyl or protected hydroxyl; and R3 is hydrogen or a carboxylic acid protecting group, the process comprising:subjecting a β-lactam halide compound of formula (2) wherein R1, R2 and R3 are as defined above, R4 is aryl or substituted aryl; X is halogen; Y is selected from the group consisting of a halogen atom, a substituted or unsubstituted lower alkylsulfonyloxy group, a substituted or unsubstituted aromatic sulfonyloxy group, a substituted or unsubstituted halogenated lower alkyl sulfonyloxy group, a substituted or unsubstituted lower alkylphosphoryloxy group and a substituted or unsubstituted aromatic phosphoryloxy group; and n is 0 to 2,to an electroreduction reaction in a reaction system comprising a positive electrode and a negative electrode, to obtain the exo-methylenepenam compound of formula (5).
- 2. A process as defined in claim 1 wherein the electroreduction reaction is conducted with a supporting electrolyte added to the reaction system.
- 3. A process as defined in claim 2 wherein the supporting electrolyte is metal perchlorate salt, ammonium perchlorate salt, ammonium halide salt, metal borofluoride salt, ammonium borofluoride salt, amine or carboxylic acid.
- 4. A process as defined in claim 1 wherein platinum, tin, aluminum, stainless steel, nickel, lead oxide, carbon, iron oxide or titanium is used as a material for the positive electrode, and platinum, tin, aluminum, stainless steel, zinc, lead, copper or carbon is used as a material for the negative electrode, in the electroreduction reaction.
- 5. A process as defined in claim 1 wherein the electroreduction reaction is practiced within a single cell without separating the positive electrode from the negative electrode.
Priority Claims (2)
Number |
Date |
Country |
Kind |
7-79485 |
Mar 1995 |
JP |
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7-79846 |
Mar 1995 |
JP |
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Parent Case Info
This is a Divisional od Application Ser. No. 09/233,426, filed Jan. 20, 1999, now U.S. Pat. No. 6,043,356, which is a Divisional of Application Ser. No. 08/732,443, filed Nov. 6, 1996, now U.S. Pat. No. 5,905,147.
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5196530 |
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Non-Patent Literature Citations (3)
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