Patent ID: 6881867

Claim:
A process for the hydroformylation of compounds containing at least one ethylenically unsaturated double bond by reaction with carbon monoxide and hydrogen in the presence of a hydroformylation catalyst comprising at least one complex of a metal of transition group VIII with at least one ligand selected from among compounds of the general formula I where A 1 and A 2 are each, independently of one another, O, S, SiR a R b , NR c or CR 5 R 6 , where R a , R b , R c , R 5 and R 6 are each, independently of one another, hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl or hetaryl, Y 1 and Y 2 are each, independently of one another, radicals containing at least one phosphorus, arsenic or antimony atom, where in each case at least two substituted or unsubstituted heteroatoms selected from among O, S and NR c , where R c is hydrogen, alkyl, cycloalkyl or aryl, are directly bound to the phosphorus, arsenic or antimony atom, and R 1 , R 2 , R 3 and R 4 are each, independently of one another, hydrogen, alkyl, cycloalkyl, heterocycloalkyl, aryl, hetaryl, COOR d , COO − M + , SO 3 R d , SO − 3 M + , NE 1 E 2 , NE 1 E 2 E 3+ X − , alkylene-NE 1 E 2 E 3+ X − , OR d , SR d , (CHR e CH 2 O) x R d , (CH 2 N(E 1 )) x R d , (CH 2 CH 2 N(E 1 )) x R d , halogen, trifluoromethyl, nitro, acyl or cyano, where R d , E 1 , E 2 and E 3 are identical or different radicals selected from among hydrogen, alkyl, cycloalkyl and aryl, R e is hydrogen, methyl or ethyl, M + is a cation, X − is an anion, and x is an integer from 1 to 120, or R 1 and/or R 3 together with two adjacent carbon atoms of the benzene ring to which they are bound form a fused ring system having 1, 2 or 3 further rings.