Preparation of 2-oxo-cyclo-alkane/alkene carboxylic acid ethylesters, useful as intermediate products to prepare macrocyclic ketones, comprises reacting diazoacetic acid ethylester with cyclo-alkanone/alkenone in the presence of Lewis acid

摘要

Preparation of 2-oxo-cycloalkane- and/or 2-oxo-cycloalkene carboxylic acid ethylesters (I) comprises reacting diazoacetic acid ethylester with cycloalkanone or cycloalkenone (II) in the presence of a Lewis acid, where the molar quantity of Lewis acid is 0.01-0.5 equivalents, related to the quantity of (II). Preparation of 2-oxo-cycloalkane- and/or 2-oxo-cycloalkene carboxylic acid ethylesters of formula (I) comprises reacting diazoacetic acid ethylester with cycloalkanone or cycloalkenone of formula (II) in the presence of a Lewis acid, where the molar quantity of Lewis acid is 0.01-0.5 equivalents, related to the quantity of (II). X : 9-19C atoms optionally substituted with 1-4C alkyl. An independent claim is included for a preparation of cycloalkanone or cycloalkenone of formula (III) comprising preparing (I) and fragmenting the obtained (I). [Image] [Image].