Claims
- 1. A process for the preparation of a compound of the formula ##SPC6##
- wherein each of R.sub.1 and R.sub.1 ' is lower alkyl, aryl or benzyl and each of R.sub.2, R.sub.3 and R.sub.4 is hydrogen or lower alkyl which comprises converting a compound of the formula ##SPC7##
- wherein R.sub.2, R.sub.3 and R.sub.4 are as above, to its enolate of the formula ##SPC8##
- wherein R.sub.2, R.sub.3 and R.sub.4 are as above and M.sup.+ is the cation of sodium, potassium or lithium, by treatment with a strong organic soluble alkali metal amide base in an inert organic solvent and treating said enolate with a compound of the formula ##EQU1## wherein R.sub.1 and R.sub.1 ' are as above and Y is chlorine, bromine or iodine, at a reduced temperature.
- 2. The process of claim 1 wherein the reduced temperature is between about -20.degree. and -80.degree.C.
- 3. The process of claim 2 wherein the reduced temperature is between about -65.degree. and -75.degree.C.
- 4. The process of claim 1 wherein M.sup.+ is lithium cation.
- 5. The process of claim 1 wherein R.sub.2, R.sub.3 and R.sub.4 are each hydrogen.
- 6. The process of claim 1 wherein R.sub.1 is methyl or ethyl.
- 7. The process of claim 1 wherein the base is lithium N-cyclohexyl N-isopropylamide.
Parent Case Info
This is a division, of application Ser. No. 497,598 filed Aug. 15, 1974, now U.S. Pat. No. 3,933,948.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3594454 |
Beriger et al. |
Jul 1971 |
|
Divisions (1)
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Number |
Date |
Country |
Parent |
497598 |
Aug 1974 |
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