Enantioselective desymmetrizing palladium catalyzed carbonylation reactions: the catalytic asymmetric synthesis of quaternary carbon center containing 1,3-dienes.

A desymmetrization protocol has been used to develop a palladium catalyzed enantioselective carbonylation process. Achiral cyclic bis-alkenyltriflates are converted to their corresponding monoester derivatives with selectivities of up to 96% ee.

Palladium-catalysed N-annulation routes to indoles: the synthesis of indoles with sterically demanding N-substituents, including demethylasterriquinone A1.

Tandem palladium-catalysed aryl and alkenyl C-N bond formation allows the synthesis of a variety of indoles bearing sterically demanding N-substituents, including the natural product demethylasterriquinone A1.

Tandem palladium-catalyzed urea arylation-intramolecular ester amidation: regioselective synthesis of 3-alkylated 2,4-quinazolinediones.

o-Halo benzoates can be combined with monoalkyl ureas in a tandem palladium-catalyzed arylation-ester amidation sequence to deliver quinazolinedione products. The reactions are regioselective for formation of the 3-N-alkyl isomers. Significant variation of both coupling partners is possible, allowing the synthesis of a diverse array of substituted quinazolinediones, exemplified by the preparation of a simple unsymmetric-dialkylated natural product.

Synthesis of ellipticine: a radical cascade protocol to aryl- and heteroaryl-annulated[b]carbazoles.

[reaction: see text] Imidoyl selanides, synthesized from amides, have been used as radical precursors of imidoyl radicals in cascade reactions. The novel radical cascade has been developed for the simple synthesis of the medicinally important aryl-annulated[b]carbazoles. The protocol has been exemplified with the high-yielding total synthesis of the anticancer alkaloid ellipticine.

Synthesis of heteroarenes using cascade radical cyclisation via iminyl radicals.

Cascade radical cyclisation involving homolytic aromatic substitution has been used to synthesise new tetracycles. Treatment of vinyl iodide radical precursors with Me(3)Sn. radicals (from hexamethylditin) yielded intermediate vinyl radicals which undergo 5-exo cyclisation onto suitably placed nitrile groups to yield intermediate iminyl radicals.