Patent ID: 8318955

Claim:
A process of preparing 2,4-dioxotetrahydrofuran-3-carboxylates of formula (I): wherein R 1 is C 1-12 alkyl, C 1-12 haloalkyl, C 5-18 aryl, C 5-18 haloaryl, C 7-19 alkylaryl or C 7-19 arylalkyl, or is alkoxyalkyl of the formula -[A-O] m -B, in which A is C 2-4 alkanediyl (alkylene), B is C 1-6 alkyl and m is 1 or 2, which process comprises: (a) reacting a compound of formula (III) wherein R 2 is selected from the group consisting of C 1-12 alkyl, C 1-12 haloalkyl, C 5-18 aryl, C 5-18 haloaryl, C 7-19 alkylaryl or C 7-19 arylalkyl, or are alkoxyalkyl of the formula -[A-O] m -B, in which A is C 2-4 alkanediyl (alkylene), B is C 1-6 alkyl and m is 1 or 2, with a base to give a deprotonated compound, wherein the base is sodium methoxide (b) reacting the deprotonated compound with a compound of formula (II) wherein Hal is selected from the group consisting of chlorine, bromine and iodine; and (c) adding water; wherein the process is effected in one pot.