METHOD FOR PRODUCING 2-OXO-CYCLOALKANE CARBOXYLIC ACID ETHYL ESTERS AND 2-OXO-CYCLOALKENE CARBOXYLIC ACID ETHYL ESTERS

摘要

The invention relates to a method for producing a 2-oxo-cycloalkane- or 2-oxo-cycloalkene carboxylic acid ethyl ester of formula (I). According to said method, a diazo ethyl acetate is reacted with a cycloalkanone or cycloalkenone of formula (II), in which X represents a saturated or mono or polyunsaturated C₉-C₁₉ chain that is optionally substituted by a C₁-C₄ alkyl group, in the presence of a Lewis acid to form the 2-oxo-cycloalkane- or 2-oxo-cycloalkene carboxylic acid ethyl ester formula (I). The molar quantity of Lewis acid that is introduced ranges between 0.01 and 0.5 equivalents, in relation to the quantity of cycloalkanone or cycloalkenone of formula (II).