Phosphine-catalysis of allenoates: Mechanism, heterocycle synthesis, and asymmetric catalysis

Catalysis employing phosphines and amines as nucleophilic triggers has emerged as a rapidly growing area of synthetic organic chemistry. In particular, phosphine-catalysis of allenoates and butynoates has proven to be useful for the development of new annulation reactions providing various carbo- and heterocycles. From readily available materials, complex chemical functionalities characteristic of those found in natural products or drug-like compounds can be synthesized. Part I (Chapters 1-3) discusses the discovery of three new phosphine-catalyzed reactions leading to the formation of dioxanes, coumarin derivatives and pyrrolines. Part II (Chapters 4 & 5) address the state of the art in asymmetric catalysis of allenoates by chiral phosphine. Chapter 4 is a current review of the field and Chapter 5 discusses a new kind of phosphine developed for the synthesis of 3-pyrrolines. Part III (Chapter 6) consists of several methods to prepare stabilized phosphonium enolate intermediates that closely resemble those evoked in the presiding transformations.