6.4 Cyclizations of (2,4-Dioxobutylidene)phosphoranes
Abstract: (2,4-Dioxobutylidene)phosphoranes can be regarded as equivalents of 1,3-dicarbonyl dianions and represent versatile building blocks in one-pot cyclizations. Their reactions with various electrophiles, such as 1,3-dicarbonyl compounds, enones, a-halo ketones, or hydrazine derivatives, allow for a convenient synthesis of a variety of carbo- and heterocyclic ring systems.
Review: Synthesis 2008, 3877-3902.
Period of investigation: 2000 – 2007
Keywords: 1,3-dicarbonyl compounds; cyclizations; heterocycles; arenes