| abstract |
Disclosed is a method for producing double metal cyanide complex catalysts of general formula M2a[M1(CN)rXt]b, wherein M2 preferably represents Co(III) or Fe(III) and M1 preferably represents Zn(II), X represents a group that is different from cyanide, forms a coordinate link to M1, and is selected among the group comprising carbonyl, cyanate, isocyanate, nitrile, thiocyanate, and nitrosyl, a, b, r, t represent integers which are selected such that the electroneutrality condition is met. Said double metal cyanide complex catalysts are produced by reacting a) a cyanometallate hydrogen acid of general formula Hw[M1(CN)r(X)t], wherein M1 and X are defined as indicated above, r and t are defined as indicated above, and w is selected such that the electroneutrality condition is met, with b) an easily protolyzable metal compound M2RW and/or M2RuYv, wherein M2 is defined as indicated above, R independently represents the anion of a very weak protonic acid having a pKs value of > 20, Y represents the anion of an inorganic mineral acid or a moderately strong to strong organic acid having a pKs value ranging from -10 to +10, w corresponds to the valence of M2, and u + v corresponds to the valence of M2, u and v amounting at least to 1, respectively. The reaction is carried out in a nonaqueous, aprotonic solvent. |