Preparing multi-metal cyanide compound, useful to prepare e.g. polyetherpolyol, comprises reacting aqueous solution of a metal salt and -cyanometallate compound to give a multi-metal cyanide compound followed by reacting with a salt

Preparation of multi-metal cyanide compound comprises reacting an aqueous solution of a metal salt (I) with an aqueous solution of a cyanometallate compound (II), optionally in the presence of an organic ligand, organic additive and/or surface active agent to give a multi-metal cyanide compound (III); and reacting (III) with a metal salt (IV), which is different from (II). Preparation of multi-metal cyanide compound comprises reacting an aqueous solution of a metal salt (I) of formula (M 1> gX n) with an aqueous solution of a cyanometallate compound (II) of formula (M 3> r[M 2>(CN) b] d), optionally in the presence of an organic ligand, organic additive and/or surface active agent to give a multi-metal cyanide compound (III) of formula (M 1> a[M 2>(CN) b] dfM 1> jX kh(H 2O)eLzP 1>); and reacting (III) with a metal salt (IV) of formula (M 4> sY 1> t), which is different from (II). M 1>a metal ion such as Zn 2+>, Fe 2+>, Fe 3+>, Co 2+>, Co 3+>, Ni 2+>, Mn 2+>, Sn 2+>, Sn 4+>, Pb 2+>, Al 3+>, Sr 2+>, Cr 3+>, Cd 2+>, Cu 2+>, La 3+>, Ce 3+>, Ce 4+>, Eu 3+>, Mg 2+>, Ti 4+>, Ag +>, Rh 2+>, Ru 2+>, Ru 3+> or Pd 2+>; M 2>a metal ion such as Fe 2+>, Fe 3+>, Co 2+>, Co 3+>, Mn 2+>, Mn 3+>, Ni 2+>, Cr 2+>, Cr 3+>, Rh 3+>, Ru 2+> or Ir 3+>; X : an anion such as halogenide, OH, sulfate, hydrogensulfate, carbonate, hydrogencarbonate, cyanide, thiocyanate, isocyanate, cyanate, carboxylate, oxalate, nitrate and/or nitrite (NO 2 ->) or uncharged species such as CO, H 2O or NO; Y 1>an anion such as halogenide, sulfate, hydrogensulfate, disulfate, sulfite, sulfonate (=RSO 3 ->, where R is 1-20C alkyl, aryl or 1-20C alkylaryl), carbonate, hydrogencarbonate, cyanide, thiocyanate, isocyanate, isothiocyanate, cyanate, carboxylate, oxalate, nitrate, nitrite, phosphate, hydrogenphosphate, dihydrogenphosphate, diphosphate, borate, tetraborate, perchlorate, tetrafluoroborate, hexafluorophosphate or tetraphenylborate; L : a ligand, mixable with water, such as alcohol, aldehyde, ketone, ether, polyether, ester, polyester, polycarbonate, urea, amide, nitrile and/or sulfide; P 1>an organic additives such as polyether, polyester, polycarbonate, polyalkyleneglycolsorbitaneester, polyalkyleneglycolglycidylether, polyacrylamide, poly(acrylamide-co-acrylic acid), polyacrylic acid, poly(acrylamide-co-maleic acid), polyacrylnitrile, polyalkylacrylate, polyalkylmethacrylate, polyvinylmethylether, polyvinylethylether, polyvinylacetate, polyvinylalcohol, poly-N-vinylpyrrolidone, poly(N-vinylpyrrol