The Synthesis of 2,5-Dialkylcyclopentanones from Aliphatic Aldehydes and Formaldehyde

Article abstract of DOI:10.1246/bcsj.54.3875

Aliphatic aldehydes react with formaldehyde in the presence of dimethylamine hydrochloride at 200 deg C to form 2,5-dialkylcyclopentanones in moderate yields.Propanal, butanal, and pentanal give 2,5-dimethyl-, 2,5-diethyl-, and 2,5-dipropylcyclopentanone respectively, but ethanal gives only a tarry material.