Back to results
US 4,307,036 AGranted
Method for preparing a mixture of stereoisomers of .alpha.-cyano-3-phenoxybenzyl 2-(4-substituted-phenyl)isovalerates
AssigneeSumitomo Chemical Company, Limited
InventorsYukio Suzuki, Kohichi Aketa, Masachika Hirano
Life of this patent
Estimating the term…
Abstract
A method for preparing .alpha.-cyano-3-phenoxybenzyl 2-(4-substituted-phenyl)isovalerates which consist substantially of or are rich in the enantiomer pair (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-(4-substituted-phenyl)isovalerate and (R)-.alpha.-cyano-3-phenoxybenzyl (R)-2-(4-substituted-phenyl)isovalerate.
Claims46
A method for preparing a mixture of isomers of compounds of the formula (I):
- ##STR6## wherein X is hydrogen, Cl or F;
- R is Cl, F, hydrogen, lower alkyl or lower haloalkyl;
- Z is oxygen or sulfur;
- and n is 0 or 1, with the proviso that when n is 0, then X is not hydrogen or Cl, said mixture consisting essentially of the enantiomer pair (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-{4-[X-(CXR-Z).sub.n ]phenyl}isovalerate and (R)-.alpha.-cyano-3-phenoxybenzyl (R)-2-{4-[X-(CXR-Z).sub.n ]phenyl}isovalerate, which method comprises precipitating said mixture as crystals from a solution of .alpha.-cyano-3-phenoxybenzyl 2-{4-[X-(CXR-Z).sub.n ]phenyl}isovalerate, and separating the crystals from the mother liquor.
1 more element
A method for preparing a mixture of isomers of compounds of the formula (II):
- ##STR7## wherein X.sup.1 is F;
- R.sup.1 is hydrogen, methyl or methyl substituted with F, and n is 0 or 1, said mixture consisting essentially of the enantiomer pair (S)-.alpha.-cyano-3-phenoxybenzyl (S)-2-{4-[X.sup.1 -(CX.sup.1 R.sup.1 -O).sub.n ]-phenyl}isovalerate and (R)-.alpha.-cyano-3-phenoxybenzyl (R)-2-{4-[X.sup.1 -(CX.sup.1 R.sup.1 -O).sub.n ]-phenyl}isovalerate, which method comprises precipitating said mixture as crystals from a solution of .alpha.-cyano-3-phenoxybenzyl 2-{4-[X.sup.1 -(CX.sup.1 R.sup.1 -O).sub.n ]-phenyl}isovalerate, and separating the crystals from the mother liquor.
Dependencies are inferred from the claim text.