Patent ID: 7745655

Claim:
A process for preparing bisphosphites of the formula I wherein R 1 , R 2 , R 3 , R 4 are independently selected from H, aliphatic, alicyclic, aliphatic-alicyclic, heterocyclic, aliphatic-heterocyclic, aromatic, aromatic-aromatic, aliphatic-aromatic hydrocarbon radical having from 1 to 50 carbon atoms, F, Cl, Br, I, —CF 3 , —OR 7 , —COR 7 , —CO 2 R 7 , —CO 2 M, —SR 7 , —SO 2 R 7 , —SOR 7 , —SO 3 R 7 , —SO 3 M, —SO 2 NR 7 R 8 , NR 7 R 8 , N═CR 7 R 8 , or NH 2 , wherein R 1 to R 4 may be covalently linked to one another, R 7 , R 8 are independently selected from H or a substituted or unsubstituted, aliphatic or aromatic hydrocarbon radical having from 1 to 25 carbon atoms, atoms, M is an alkali metal ion, alkaline earth metal ion, ammonium ion, or phosphonium ion, Q is a divalent aliphatic, alicyclic, aliphatic-alicyclic, heterocyclic, aliphatic-heterocyclic, aromatic, or aliphatic-aromatic hydrocarbon radical having from 1 to 50 carbon atoms, Z, Y are each Cl, Br, or I, W, X are independently selected from an aliphatic, alicyclic, aliphatic-alicyclic, heterocyclic, aliphatic-heterocyclic, aromatic, aromatic-aromatic, or aliphatic-aromatic hydrocarbon radical having from 1 to 50 carbon atoms and may be covalently linked to one another, the process comprising carrying out the reaction sequence wherein the reaction steps a), b) and c) are carried out in aprotic and nonpolar solvents, the adduct base•HY or base•HZ is filtered off after at least one of the reaction steps a), b) and c) and the end product is isolated and purified.