| abstract |
D-2-phenoxypropionic acids, in which the ring may be substituted by halogen and/or methyl, are prepared by reacting an alkali metal salt, dextrorotatory in water, of 2-chloropropionic acid with an alkali metal phenate, followed by acidification. The alkali metal 2-chloropropionate is preferably prepared in situ by action of an alkali metal base on an ester (e.g. the methyl ester) of 2-chloropropionic acid at 5-35 DEG C. Examples describe the preparation of D - 2 - (2 - methylphenoxy)-, -(4 - chloro - 2 -methylphenoxy)-(2,4,5 - trichlorophenoxy)-and-(2,4-dichlorophenoxy)-propionic acids. Methyl 2-chloropropionate is made by reacting D-methyl lactate with SOCl2. |