GLYCEROL DERIVATIVES AND HERBICIDAL COMPOSITIONS

1427918 Glycerol ketals SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ NV 24 May 1973 [26 May 1972] 24900/72 Heading C2C The invention comprises compounds (I) and (II), where R 1 is carboxy, alkyl, alkoxy, alkoxycarbonyl, mono-N-substituted carbamoyl, or aryl or a group -C(Y)=NOZ, where Y is alkyl or alkoxycarbonyl and Z is hydrogen, alkyl or mono-N-substituted carbamoyl; R 2 is hydrogen or alkyl; or R 1 and R 2 form a polymethylene ring; and R 3 is optionally halo-substituted aralkyl, thie preparation by reacting a diol or with a compound R 1 COR 2 or a non-cyclic acetal thereof in the presence of an acid catalyst or by reacting a compound (VI) or (VII) with R 3 halide in the presence of a strong base and, if desired, in resulting compounds, converting free carboxylic acids to amides or O-carbamoylating, O-unsubstituted oximes. The compounds of the invention are used to combat weeds at a locus and the invention includes herbicidal compositions comprising the compounds and a suitable carrier and/or surfactant.