Abstract: The invention relates to a method for producing compounds of general formula (I), wherein Rt represents an oxocyclohexyl radical which is optionally substituted by a hydroxyl radical, an alkoxy radical, and/or alkyl radicals, or an oxocyclohexenyl radical which is optionally substituted by a hydroxyl radical, an alkoxy radical, and/or alkyl radicals, the oxo groups being in the form of an acetal, a ketone, or an enol ether, and R2 represents a hydroxy group or a protective group which can be transformed into a hydroxy group by means of hydrolysis. A compound of general formula (II) is cathodically reduced in a divided or partially divided electrolysis cell at a pH value of between 2 and 9.

Abstract: A process for an electrochemical reduction of a reducible dye by contacting said reducible dye with a cathode comprising a support of an electrically conductive material and an electrically conductive, cathodically polarized layer formed thereon in situ by alluviation comprises conducting said electrochemical reduction in the presence of a base.

Abstract: A process for an electrochemical reduction of a reducible dye by contacting said reducible dye with a cathode comprising a support of an electrically conductive material and an electrically conductive, cathodically polarized layer formed thereon in situ by alluviation comprises conducting said electrochemical reduction in the presence of a base.

Abstract: A process is described for preparing diacetals of glyoxal by reacting from 40 to 75% by weight aqueous glyoxal with monohydric alcohols in the presence of an acid catalyst, which comprises leaving a liquid mixture which, at the beginning of the reaction, comprises alcohol and glyoxal in a molar ratio of at least 15:1 and also water in a concentration of not more than 8% by weight in contact with the acid catalyst until concentration in the reaction mixture of the diacetal formed reaches at least 70% of the equilibrium concentration without more than 5% by weight of the alcohol used having already been distilled off.

Abstract: The present invention relates to a process for preparing 2-cyclo-alkenones of the formula I ##STR1## which comprises subjecting a 2-alkoxycycloalkanone and/or a 2-hydroxyalkanone ketal, in which n is an integer from 0 to 20, m is 0, 1, 2 or 3 and R is alkyl, alkylaryl, aryl, arylalkyl, alkenyl or alkynyl, to an elimination reaction in the gas phase on an acidic heterogeneous catalyst.