Method for the manufacture of dialkylphosphites

A method for the manufacture of di-alkylphosphites starting from a P—O component containing from 1 to 6 P—O—P bonds in the molecule comprising the step of:

• a) reacting a mixture of R′OH and P—O, expressed in molar ratios of R′OH:P—O of at least 1:1 to 6:1,
• wherein R′ is selected from alkyl groups having from 5 to 20 carbon atoms in branched or linear configuration;
• and
• an acid ester having the formula:
• R—C(O)OR′
• wherein R′ has the meaning as stated above, wherein R represents an alkyl chain having from 1 to 6 carbon atoms, wherein the minimum number of mole(s) of R—C(O)OR′ per P atom in the P—O molecule, required for the method is represented by z and z is determined by the formula z=2n−m, wherein m is the number of P—O—P bonds in the P—O molecule, and n is the number of P atoms in the P—O molecule;
• by adding the P—O component to the R′OH, simultaneously with or separately from the acid ester;
• at a temperature in the range of from 40° C. to 180° C. for a period of from 10 minutes to 10 hours under simultaneous distillation of the carboxylic acid formed.