Michael-type addition of 1,8-diazabicyclo[5.4.0]undec-7-ene to dimethyl acetylenedicarboxylate
Abstract
Michael reaction of DBU 1 with dimethyl acetylenedicarboxylate 2 and subsequent intramolecular condensation of the adduct gives a tricyclic derivative 6; a mechanism for the formation of 6 is proposed and an X-ray crystal structure of 6 is presented.