Patent ID: 8263788

Claim:
A process for preparing 1,3-dioxolan-2-one of formula 3 wherein R 1 and R 2 each independently of one another represent hydrogen or an aryl or heteroaryl group, while the aryl or heteroaryl group may optionally be mono- or polysubstituted in each case; R 4 and R 5 are each independently of one another selected from among hydrogen, C 1 -C 6 -alkyl, or R 4 and R 5 together form a saturated or mono- or polyunsaturated carbocyclic or heterocyclic ring which may contain one or more heteroatoms, selected from S, N or O, each of which may optionally be mono- or polysubstituted independently of one another, while R 4 and R 5 cannot both simultaneously be hydrogen; comprising reacting in one step a 2-hydroxycarboxylic acid ester of formula 1 wherein R 1 and R 2 are as hereinbefore defined and R 3 denotes methyl, ethyl, propyl, isopropyl, isopropenyl, butyl, N-succinimide, N-phthalimide, phenyl, nitrophenyl, fluorophenyl, pentafluorophenyl, vinyl, 2-allyl, in a suitable solvent with the addition of a suitable tert-alkoxide basic catalyst, in the presence of zeolite, with a compound of formula 2 wherein R 4 and R 5 are as hereinbefore defined.