Abstract: Pyrocatechin derivatives of formula I wherein R illustrates a group of formulae Ia, Ib, Ic or Id R1 is 4-halogen-but-2-enyl, R2 is lower alkyl or cycloalkyl, R3 is lower alkoxy and R4 is lower alkoxy lower alkoxy, or, where R is a group of formula (Ia), it is hydroxy, hydroxy lower alkoxy or a group of formula Ie R5 is reactive esterified hydroxy, R6 is azido and R7 is lower alkyl, lower alkenyl, cycloalkyl or aryl lower alkyl, and their salts, are valuable intermediates in the production of active ingredients for medicaments.

Abstract: The invention relates to a novel and technically advanced process for producing 5-cyano-5H-dibenz[b,f]azepine by reacting 5H-dibenz[b,f]azepine with a halocyanogen in the presence of strongly polar substances. 5-Cyano-5H-dibenz[b,f]azepine can be used as starting material for producing 5-carbamyl-10(11)-oxo-10,11-dihydro-5H-dibenz[b,f]azepine, which is known to have central-depressant, anticonvulsive and central-muscle-relaxing activity.

Abstract: The invention relates to a process for inverting the configuration in optically active compounds of the formula ##STR1## in which Ar.sub.1 represents a monocyclic or polycyclic, carbocyclic or heterocyclic radical that has at least one ring of aromatic character and is bonded to the oxygen atom by way of a ring carbon atom, preferably of the ring of aromatic character, andR.sub.1 represents an optionally substituted aliphatic, cycloaliphatic or araliphatic hydrocarbon radical,or the salts thereof, characterized in that an optically active compound of the formula ##STR2## having a R(+) or S(-) configuration, in which R.sub.2 represents a monocyclic or polycyclic, carbocyclic or heterocyclic radical, or an optionally substituted aliphatic, cycloaliphatic or araliphatic hydrocarbon radical,is converted, by treating with a strong oxygen-containing inorganic or organic acid or halides thereof, into an optically active compound of the formula ##STR3## in which x.sup..crclbar.

Abstract: The invention relates to a process for inverting the configuration in optically active compounds of the formula ##STR1## in which Ar.sub.1 represents a monocyclic or polycyclic, carbocyclic or heterocyclic radical that has at least one ring of aromatic character and is bonded to the oxygen atom by way of a ring carbon atom, preferably of the ring of aromatic character, andR.sub.1 represents an optionally substituted aliphatic, cycloaliphatic or araliphatic hydrocarbon radical,or the salts thereof, characterised in that an optically active compound of the formula ##STR2## having a R(+) or S(-) configuration, in which R.sub.2 represents a monocyclic or polycyclic, carbocyclic or heterocyclic radical, or an optionally substituted aliphatic, cycloaliphatic or araliphatic hydrocarbon radical,is converted, by treating with a strong oxygen-containing inorganic or organic acid or halides thererof, into an optically active compound of the formula ##STR3## in which X.sup..crclbar.