Claims
- 1. A process for the preparation of cyclopropane carboxylic acid derivatives of the formula ##STR16## wherein Z is selected from the group consisting of --CN and --COOR.sub.1, R.sub.1 is alkyl of 1 to 6 carbon atoms and R.sub.2 and R.sub.3 are alkyl of 1 to 4 carbon atoms or taken together with the carbon atom to which they are attached form a carbon homocycle of 3 to 6 carbon atoms comprising reacting at low temperatures of -90.degree. to -30.degree. C. in a solvent in the presence of a strong base a compound of the formula ##STR17## wherein Z has the above definition and R is alkyl of 1 to 6 carbon atoms or together form a polymethylene of 2 to 3 carbon atoms with a sulfone of the formula ##STR18## wherein R.sub.2 and R.sub.3 have the above definitions and Y is an aromatic group followed by aqueous treatment to obtain a compound of the formula ##STR19## wherein Y, R, R.sub.2, R.sub.3 and Z have the above definitions, reacting the latter at a low temperature in a solvent with a strong base while letting the temperature rise to obtain a compound of the formula ##STR20## wherein R, R.sub.2, R.sub.3 and Z have the above definitions of the cis/trans configuration richer in the trans isomer and reacting the latter with a strong base in an aqueous media followed by acidification to obtain a compound of the formula ##STR21## wherein R, R.sub.2 and R.sub.3 have the above definitions having the same configuration as the compound of formula I, reacting the compound of formula Va with an acid agent in an aqueous media to obtain the corresponding acid of formula I with the same configuration as the compound of formula Va and optionally treating the latter with a weak base at room temperature to obtain the acid of formula I with a trans configuration.
- 2. A process for the preparation of cyclopropane carboxylic acid derivatives of the formula ##STR22## wherein R.sub.1 is alkyl of 1 to 6 carbon atoms and R.sub.2 and R.sub.3 are alkyl of 1 to 4 carbon atoms or taken together with the carbon atom to which they are attached form a carbon homocycle of 3 to 6 carbon atoms comprising reacting at low temperatures of -90.degree. to -30.degree. C. in a solvent in the presence of a strong base a compound of the formula ##STR23## wherein R is alkyl of 1 to 6 carbon atoms or together form a polymethylene of 2 to 3 carbon atoms with a sulfone of the formula ##STR24## wherein R.sub.2 and R.sub.3 have the above definitions and Y is an aromatic group followed by aqueous treatment to obtain a compound of the formula ##STR25## wherein Y, R, R.sub.2, R.sub.3 and Z have the above definitions, reacting the latter at a low temperature in a solvent with a strong base while letting the temperature rise to obtain a compound of the formula ##STR26## wherein R, R.sub.2, R.sub.3 and Z have the above definitions of the cis/trans configuration richer in the trans isomer and reacting the compound of formula V with an acid agent in an aqueous media to obtain the corresponding compound of formula I with the same configuration as the compound of formula V and optionally treating the latter with a weak base at room temperature to obtain the compound of formula I with a trans configuration.
- 3. The process of claim 1 or 2 wherein the temperature of the reaction mixture of the reaction of the compounds of formulae II and III at a low temperature is allowed to rise to obtain directly the compound of formula V without isolation of the compound of formula IV.
- 4. The process of claim 1, wherein R.sub.2 and R.sub.3 are methyl.
- 5. The process of claim 1 or 2 wherein the strong base present in the reaction of the compounds of formulae II and III is selected from the group consisting of alkali metal alcoholates, alkali metal hydrides, amide of diisopropylamine, alkali metal amides, aryllithium and alkyllithium.
- 6. The process of claim 5 wherein the solvent for the reaction is a polar solvent selected from the group consisting of dimethoxyethane, dimethylformamide, tetrahydrofuran, hexamethylphosporotriamide and mixtures thereof with hydrocarbons.
- 7. The process of claim 1 wherein the treatment of the compound of formula IV with a strong base is effected at -60.degree. to -10.degree. C.
- 8. The process of claim 1 or 2 wherein the temperature to which the mixture containing the compound of formula IV is allowed to rise to +10.degree. to 30.degree. C.
- 9. The process of claim 1 wherein the strong base reacted with a compound of formula V wherein Z is --CN or --COOR.sub.1 is an alkali metal hydroxide.
- 10. The process of claim 1 wherein the acid hydrolysis of the ketal is effected with an acid selected from the group consisting of sulfuric acid, hydrochloric acid and phosphoric acid.
- 11. The process of claim 1 or 2 wherein the weak base is an alkali metal carbonate.
Priority Claims (1)
Number |
Date |
Country |
Kind |
80 20476 |
Sep 1980 |
FRX |
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PRIOR APPLICATION
This application is a continuation of U.S. patent application Ser. No. 300,927 filed Sept. 10, 1983, now abandoned.
US Referenced Citations (3)
Non-Patent Literature Citations (3)
Entry |
Devos, Tetrahedron Letters, pp. 3911-3914 (1976). |
Allinger, "Organic Chemistry", pp. 477-478, 532-537 and 585 (1971). |
House, "Modern Synthetic Reactions", 2nd Ed, Benjamin Cummings Publg. Co., Menlo Park, Calif., pp. 598, 602 & 614 (1972). |
Continuations (1)
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Number |
Date |
Country |
Parent |
300927 |
Sep 1983 |
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