10^th European Organic Chemistry Congress

Biography

Biography: Pawel Woznicki

Abstract

Organophosphorus compounds are one of the main classes of ligands used in transition metal-catalyzed reactions such as cross-coupling, catalytic hydrogenation and olefin metathesis. Among them cycloalkyl and P-heterocyclic phosphines constitute an important subgroup with good σ-donating ability and medium to high steric hindrance, these properties render them suitable for palladium- and nickel-catalyzed cross-coupling of less reactive or deactivated substrates such as aryl chlorides with electron-donating substituents, aryl sulfonates, aryl carboxylates, and aryl ethers.

We have developed a new method of the synthesis of cyclic di- and monoarylphosphine derivatives through haloalkylation of simple secondary or tertiary phosphine-boranes and sulfides followed by α-metallation and intramolecular nucleophilic substitution of halide at the terminal carbon atom. Depending on the properties of the phosphorus group and the length of the haloalkyl substituent monoarylphosphine derivatives led to the formation of P-cycloalkyl or P-heterocyclic products. The use of chiral butyllithium-sparteine base allowed the formation of chiral non-racemic cycloalkylphosphine analogues which were used to synthesize diphosphine ligand precursors via iron-mediated homocoupling.