Process for the production of acetals from carbon dioxide

A process for the production of a compound of the formula (I)

• wherein
• each R1 is independently from each other selected from C1-C40 alkyl, which is unsubstituted or substituted with 1, 2, 3, 4 or 5 substituents selected from OH, halogen, C1-C6 alkoxy or C6-C20 aryl;
• or both R1 form together a divalent bridging group R2 selected from linear C2-C9-alkanediyl, wherein the alkanediyl is unsubstituted or substituted by 1, 2, 3 or 4 substituents selected from OH, halogen, C1-C6 alkyl or C1-C6 alkoxy;
• the process comprising at least one reaction step, in which carbon dioxide and hydrogen are reacted with at least one compound of the general formulae (II.a) or (II.b)
• R1—OH (II.a),
• HO—R2—OH (II.b),
• wherein
• R1 is as defined above;
• R2 is a divalent group selected from linear C2-C9 alkanediyl, wherein the alkanediyl is unsubstituted or substituted by 1, 2, 3 or 4 substituents selected from OH, halogen, C1-C6 alkyl or C1-C6 alkoxy;
• in the presence of
• at least one transition metal catalyst complex, comprising at least one polydentate ligand containing at least three phosphorus atoms which are capable of coordinating to the transition metal, wherein the transition metal is selected from metals of groups 7, 8, 9 and 10 of the periodic table of the elements according to IUPAC;
• and
• at least one monodentate ligand containing one phosphorus atom;
• and
• at least one Lewis acid.