Et 2-phenoxypropionates (1) were condensed with substituted acetophenones in cyclohexaneltoluene in presence of NaH under boiling to resp. racernic 4-phenoxy-1,3-pentanedione (11) derivatives. The (R)-l were synthesized by condensation of Et (S)-(-) lactate with TbsCl in MeCN in presence of Et3N with following replacment with substituted phenols in presence of Na,CO 3 and then similary converted to resp. (R)(+)-I/. The It were chlorinated with SO,Cl-2 in boiling CCI4 to resp. 2-C-II and then converted to the hydroxyimino derivatives with NaNO2 at below 8 degrees C optionally with following methoxylation with Me,SO, in boiling MeOH. The 2-CI-II were also substituted with derivatives of PhNH2, PhNH NH2, and 1,2,4-triazole to resp. 2-aminosubstituted II. The 2-Cl-II was also substituted with inorg. anions in boiling MeCN. The 4(4-chlorophenoxy)-2-chloro-l-phenyl-1,3-pentanedione was also substituted with thiourea to 2-amino-4-fl-(4-chlorophenoxy)ethyl]-5-benzothiazole. The synthesized mainly new compds. showed a herbicide activity against several troublesome weed species and controlled some pathogenic fungi.