Abstract: Optically active compounds of formula ##STR1## in which R is either a H.sub.3 C--, (CH.sub.3).sub.3 C--, (CH.sub.3).sub.3 CO--, C.sub.6 H.sub.5 CH.sub.2 O--, C.sub.6 H.sub.5 --, o-NO.sub.2 C.sub.6 H.sub.4 --, p-NO.sub.2 C.sub.6 H.sub.4 -- or a p-CH.sub.3 C.sub.6 H.sub.4 -group, or salts or lower alkyl esters thereof. The compounds are prepared by the following sequence of reaction steps:(a) there is started from a racemic mixture of a compound according to said formula in which R=a C.sub.6 H.sub.5 group,(b) cinchonidine, D(--)-2-aminobutanol-1 or a derivative thereof is added to this compound as resolving agent,(c) the D(--)-salt of the resolving agent formed is crystallized out and isolated,(d) if necessary, this salt is further purified of the L-isomer by recrystallization,(e) the pure D(--)-salt is hydrolysed in order to remove the resolving agent,(f) the D(--)-S-benzoyl-.beta.-mercaptoisobutyric acid thus liberated is won and, if necessary, purified, and(g) if desired, the C.sub.6 H.sub.

Abstract: Resolution of DL-S-benzoyl-.beta.-mercaptoisobutyric acid into its optical antipodes is effected by treating the DL-acid in solution with D-(+)-N-benzyl-.alpha.-phenethylamine. The D(-)-S-benzoyl-.beta.-mercaptoisobutyric acid itself as well as its salts, esters or derivatives can be obtained advantageously by this process.

Abstract: The explosive 2,4,6-trinitrotoluene (TNT) is desensitized by dissolving it in oleum of from 10 to 40% (by weight) in strength. The solutions formed preferably contain at least 400 g and at most 480 g of dissolved TNT per liter of oleum in oleum of 20-25% strength. They are especially useful for the preparation of phloroglucinol.

Abstract: Preparation of a 3-thienylmalonic acid or a diester thereof comprising reacting in a polar solvent in the presence of a copper (I) halide a thiophene compound of formula: ##STR1## wherein X=I or Br,R.sub.1 =H or a C.sub.1-4 alkyl group,R.sub.2 =H or a C.sub.1-2 alkyl group andR.sub.3 =H or a C.sub.1-2 alkyl group,with the proviso that R.sub.2 and R.sub.3 cannot be an alkyl group simultaneously, with a mono-deprotonated methylene compound of formula: ##STR2## wherein a cation is present and Z'=Z" is CN or COOR in which R is a C.sub.1-4 alkyl group, or Z'=CN and Z"=COOR' in which R' is a C.sub.1-2 alkyl group, followed by hydrolysis by methods known per se to get the corresponding free acid.

Abstract: A method for preparing a 3-iodothiophene from a corresponding 3-bromothiophene comprising reacting with copper(I)iodide in a polar aprotic solvent and at an elevated temperature a 3-bromothiophene of formula ##STR1## wherein R.sub.1 is H or a C.sub.1-4 alkyl group,R.sub.2 is H or a C.sub.1-2 alkyl group andR.sub.3 is H or a C.sub.1-2 alkyl group,With the proviso that not more than one of R.sub.2 and R.sub.3 is an alkyl group.

Abstract: A 1,3,5-trialkoxy benzene having 1-2 carbon atoms in each of the alkoxy-groups is prepared at high overall yields, with minimal formation of hazardous or polluting by-products, by reacting 1,3,5-tribromo benzene with an alkalimetal alcoholate having 1-3 carbon atoms in the molecule in the presence of a copper salt, e.g. cuprous iodide or cupric chloride, and an aprotic solvent such as e.g. dimethylformamide. The product is readily recovered from the reaction mixture in an overall yield as high as 90%.

Abstract: 4-Pyridylthioacetic acid is prepared economically without the formation of any noxious substance by (1) reacting a 4-nitropyridyl-N-oxide with a lower alkyl thioglycolate or with thioglycolic acid to form 4-thioglycolic acid (or 4-thioglycolate)-pyridyl-N-oxide, (2) reducing the latter oxide in the form of its 4-alkyl thioglycolate to obtain the corresponding 4-pyridylthioglycolic acid ester, and (3) converting said ester into a 4-pyridylthioacetic acid by saponification followed by acidification. When a lower alkyl thioglycolate is used for the reaction in step (1), step (2) can follow directly for reduction of the reaction product, and high yields are obtained.