Transition-metal catalysis in Michael addition of β-dicarbonyls: Tuning of the reaction conditions

Abstract

(2,4-Pentanedionato)copper(I), bis(2,4-pentanedionato)copper(II), and tris(2,4-pentadionato)iron(III) together with boron trifluoride etherate catalyze Michael addition of β-dicarbonyls V and VI to 2-cyclohexen-1-one (IV), 2-cyclopenten-1-one (IX), 2-methyl-2-cyclopenten-1-one (X), and 3-thienylidenemalonaldehyde (XIX).