Process for the preparation of 3,3-dimethyl-cyclopropane-1,2-dicarboxylic acid esters, intermediates therefor and their production

摘要

A novel process for the preparation of 3,3-dimethylcyclopropane- 1,2-dicarboxylic acid esters of the formula I IMAGE in which R and R' have the meaning indicated in the description, which is characterised in that 1,3-dichloro-2,2-dimethylpropane-1,3-dicarboxylic acid esters of the formula II IMAGE are reacted at temperatures between 20 and 200 DEG C with zinc, if appropriate in the presence of a diluent, and novel 1,3-dichloro-2,2-dimethylpropane-1,3-dicarboxylic acid esters of the formula II and processes and intermediates for their preparation.