Abstract: A system which is suitable as a catalyst for the hydrocyanation of olefinically unsaturated compounds and comprises a) Ni(0) b) a compound which complexes Ni(0) as a ligand and contains trivalent phosphorus, c) a Lewis acid and d) a compound of the formula M Rn where M: Al or Ti R: identical or different monovalent alkoxy radicals, in which case a plurality of alkoxy radicals may be bonded together, and additionally, in the case that M=Al, R may be identical or different monovalent alkyl radicals, in which case a plurality of alkyl radicals may be bonded together or one or more alkyl radicals may be bonded to one or more of the abovementioned alkoxy radicals, n: valency of M, and processes for hydrocyanating an olefinically unsaturated compound in the presence of such a system.

Abstract: The invention relates to phosphinite phosphites I of formula 1, 2, 3, 4, 5 or 6 and mixtures thereof, wherein R1, R2, R4 independently represent an alkyl or alkylene group with 1 to 8 carbon atoms, provided that at least one of the groups R1, R2, R4 is different from H; R5 to R22 independently represent H, an alkyl or alkylene group with 1 to 8 carbon atoms; R3 is H, methyl or ethyl; X is F, Cl or CF3, if n=1 or 2 and X is H, if n=0.

Abstract: A process for dewatering hydrocyanic acid by distillation, which includes distilling crude hydrocyanic acid containing from 50 to 99.9% by weight of HCN, from 0.1 to 40% by weight of water, from 0 to 15% by weight of carbon oxides and optionally from 0.01 to 1% by weight of an involatile stabilizer, at a pressure of from 1 bar to 2.5 bar, a bottom temperature of from 100° C. to 130° C. and a top temperature of from 25° C. to 54° C., in the absence of a volatile stabilizer, in a distillation column to obtain a top draw stream containing purified, anhydrous hydrocyanic acid and carbon oxides and a bottom draw stream including water and, optionally, the involatile stabilizer.

Abstract: A process for isomerizing cis-2-pentenenitrile to trans-3-pentenenitrile in the presence of aluminum oxide as a catalyst, wherein the aluminum oxide has a BET surface area of at least 50 m2/g.