The Baylis-Hillman reaction of various aryl aldehydes with methyl vinyl ketone and acrylonitrile in the thermomorphic binary system (DMF/cyclohexane, 1/1, v/v) has been investigated. The phase selectively soluble alkyl-modified dendritic DMAP catalyst could be easily recycled via phase separation which was induced by cooling the temperature from 60 degrees C to room temperature. The corresponding Baylis-Hillman adducts were obtained in good yields and the recycled and reactivated dendritic catalyst almost gave the same results. (c) 2005 Elsevier B.V. All rights reserved.