Claims
- 1. A process for preparing a cepham compound which comprises reacting a compound of the formula ##STR12## with at least a molar ratio of sodium or potassium iodide at a temperature of from about 40.degree. C. to about 80.degree. C., to produce the 3-exomethylene or 3-keto cepham of the formula ##STR13## in which, in the above formulae, R.sub.1 is a carboxy protecting group; R is the residue of an imide derived from a dicarboxylic acid; R.sub.2 is =CH.sub.2 or =O; and X is chloro or bromo.
- 2. Process of claim 1, in which the reaction is carried out in the presence of a ketone solvent.
- 3. Process of claim 2, in which the reaction is carried out in the presence of acetone.
- 4. Process of claim 2, in which R.sub.1 is the residue of an ester function which is removable by acid treatment or hydrogenation.
- 5. Process of claim 2, in which R.sub.1 is methyl, benzyl, p-nitrobenzyl, p-methoxybenzyl, benzylhydryl, t-butyl, or trimethylsilyl.
- 6. Process of claim 2, in which R.sub.1 is p-nitrobenzyl.
- 7. Process of claim 2, in which R is phthalimido.
- 8. Process of claim 7, in which R.sub.2 is =CH.sub.2.
- 9. Process of claim 8, in which X is chloro.
- 10. Process of claim 7, in which R.sub.2 is =O.
- 11. Process of claim 10, in which X is chloro.
Parent Case Info
This is a division of application Ser. No. 615,154, filed Sept. 19, 1975, and now U.S. Pat. No. 4,024,152 issued May 17, 1977.
US Referenced Citations (9)
Divisions (1)
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Number |
Date |
Country |
Parent |
615154 |
Sep 1975 |
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