| abstract |
Lactones are prepared by catalytic carbonylation of oxiranes using a catalyst system comprising a) at least one carbonylation catalyst A comprising uncharged or anionic transition metal complexes of metals of groups 5 to 11 of the Periodic Table of the Elements and b) at least one chiral Lewis acid B, n with the exception of [(salph)Al(THF) 2 ][Co(CO) 4 ], as catalyst. |