Method for producing polyetherols by ring-opening polymerisation of alkylene oxides

A process for preparing polyetherols by ring-opening polymerization of alkylene oxides onto H-functional initiator molecules, which comprises at least one process step a) in which a compound of the formula (I)

• M′aM″b(OH)c Od*Ae*Lf (I),
• where
• M′ is a metal ion selected from groups IA, IIA of the Periodic Table and Ni or Zn, and mixtures thereof,
• M″ is a metal ion selected from groups IIIA, IVA, IB to VIIIB of the Periodic Table and As, Sb and Bi, and mixtures thereof,
• A is at least one singly charged or multiply charged, inorganic or organic anion,
• L is at least one inorganic or organic ligand,
• where
• a, b are rational numbers greater than zero,
• c, d, e, f are rational numbers greater than or equal to zero,
• c and d must not simultaneously be zero,
• a, b, c, d, e and f are selected such that the compound is electrically neutral,
• applied to a solid inert support or incorporated in the latter or molded to form a shaped body is used as catalyst,
• and at least one process step b) in which a multimetal cyanide compound of the formula (II)
• M1a[M2(CN)b(A)c]d·fM1gXn·h(H2O)·eL (II)
• where
• M1 is at least one metal ion selected from the group consisting of Zn2+, Fe2+, Co3+, Ni2+, Mn2+, Co2+, Sn2+, Pb2+, Mo4+, Mo6+, Al3+, V4+, V5+, Sr2+, W4+, W6+, Cr2+, Cr3+, Cd2+,
• M2 is at least one metal ion selected from the group consisting of Fe2+, Fe3+, Co2+, Co3+, Mn2+, Mn3+, V4+, V5+, Cr2+, Cr3+, Rh3+, Ru2+, Ir3+ and M1 and M2 are identical or different,
• A is at least one anion selected from the group consisting of halide, hydroxide, sulfate, carbonate, cyanide, thiocyanate, isocyanate, cyanate, carboxylate, oxalate and nitrate,
• X is at least one anion selected from the group consisting of halide, hydroxide, sulfate, carbonate, cyanide, thiocyanate, isocyanate, cyanate, carboxylate, oxalate and nitrate,
• L is at least one water-miscible ligand selected from the group consisting of alcohols, aldehydes, ketones, ethers, polyethers, esters, ureas, amides, nitriles and sulfides, and
• a, b, c, d, g, and n are selected such that the compound is electrically neutral, and
• e is the coordination number of the ligand,
• e and f are fractional numbers or integers greater than or equal to 0,
• h is a fractional number of integer greater than or equal to 0,
• applied to a solid, inert support or incorporated in the latter or molded to form a shaped body or in powder or paste form is used as catalyst.