Process for preparing dihydrofuranone derivatives.

摘要

The present invention provides a process for preparing dihydrofuranone derivative of the fornula (III): <CHEM> wherein R<1> and R<3> are individually lower alkyl, and R<2> is hydrogen or lower alkyl, by reacting a dihydrofuranone derivative of the formula (I): <CHEM> wherein R<1> is as defined above, with a malonic acid derivative of the formula (II): <CHEM> wherein R<2> and R<3> are as defined above, in the presence of an alkalimetal alkoxide and/or an alkalimetal hydroxide.