Claims
- 1. A process for the preparation of a diastereomer of the formula Ia ##STR22## where R.sup.1 is hydrogen, alkyl of 1 to 6 carbon atoms, alkenyl of 2 to 4 carbon atoms or unsubstituted or substituted benzyl, R.sup.2 is methyl, ethyl or vinyl, R.sup.3 is alkyl of 1 to 6 carbon atoms, cyclohexyl, methylcyclohexyl or unsubstituted or substituted benzyl, the substitutions on the R.sup.1 and R.sup.3 benzyl groups being 1 or 2 halogen, C.sub.1 -C.sub.4 -alkyl, trifluoromethyl or C.sub.2 -C.sub.4 -alkenyl substituents, and the asymmetric centers of the molecule have an RR or SS configuration, wherein a ketone of the formula II ##STR23## where R.sup.3 has the above meanings, is subjected to a diastereoselective Grignard reaction with a compound of the formula R.sup.2 MgX, where R.sup.2 has the meanings given above and X is Cl, Br or I, and, if required, the resulting alcohol compound of the formula Ia ##STR24## where R.sup.2 and R.sup.3 have the above meanings, R.sup.1 is hydrogen and C.sub.1 and C.sub.2 have an RR or SS configuration, is converted to an ether of the formula Ia, where R.sup.1 has the meanings stated above with the exception of hydrogen.
- 2. A process for the preparation of the diastereomer of the formula Ib ##STR25## where R.sup.1 is hydrogen, alkyl of 1 to 6 carbon atoms, alkenyl of 2 to 4 carbon atoms or unsubstituted or substituted benzyl, R.sup.2 is methyl, ethyl or vinyl, R.sup.3 is alkyl of 1 to 6 carbon atoms, cyclohexyl, methylcyclohexyl or unsubstituted or substituted benzyl, the substitutions on the R.sup.1 and R.sup.3 benzyl groups being 1 or 2 halogen, C.sub.1 -C.sub.4 -alkyl, trifluoromethyl or C.sub.2 -C.sub.4 -alkenyl substituents, and the asymmetric centers of the molecule have an RR or SS configuration, wherein a ketone of the formula III ##STR26## where R.sup.2 and R.sup.3 have the meanings stated is subjected to a diastereoselective Grignard reaction with a compound of the formula IV ##STR27## where X is Cl, Br or I, and, if required, the resulting alcohol compound of the formula Ib ##STR28## where R.sup.2 and R.sup.3 have the above meanings, R.sup.1 is hydrogen and C.sub.1 and C.sub.2 have an RS or SR configuration, is converted to an ether of the formula Ib, where R.sup.1 has the meanings stated above, with the exception of hydrogen.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3504897 |
Feb 1985 |
DEX |
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Parent Case Info
This application is a division of application Ser. No. 829,774, filed on Feb. 13, 1986, now abandoned.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
4411687 |
Zeeh et al. |
Oct 1983 |
|
4436548 |
Zeeh et al. |
Mar 1984 |
|
4554285 |
Zeeh et al. |
Nov 1985 |
|
Foreign Referenced Citations (3)
Number |
Date |
Country |
015639 |
Sep 1980 |
EPX |
0019153 |
Nov 1980 |
EPX |
2102796 |
Feb 1983 |
GBX |
Divisions (1)
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Number |
Date |
Country |
Parent |
829774 |
Feb 1986 |
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