Synthesis of Heterocycles via Palladium-Catalyzed Carbonylations

Palladium-catalyzed bond-forming processes (e.g., C-C, C-X, C-Y; X ) F; Y ) NR2, OR, SR, etc.) represent essential tools for the synthetic chemist. A fascinating myriad of adventurous and unique Pd-catalyzed transformations are routinely found as key steps in target-oriented syntheses, affording complex natural products, functional advanced materials, fluorescent compounds, pharmaceutical lead compounds, and other high-value commercial products. Innovative Pd catalyst design, the identification of new synthetic methodologies, and the acquirement of detailed mechanistic insight, spanning both homogeneous and heterogeneous fields, underpin the numerous developments seen in this area over the past 40 years. Most commonly, Pd-catalyzed bond-forming processes involve Pd0/PdII complexes as intermediates. In recent times, the involvement of PdIV complexes have been implicated in many new synthetic methodologies, for which important advances have been made in the last 5 years or so. While observing the emergence of catalytic PdIV chemistry, particularly in organic synthesis, we identified the need to comprehensively review this area, which draws on aspects from both inorganic (organometallic) and organic chemistry fields. The historical background to organopalladium(IV) chemistry is therefore detailed. We have selected a wide range of diverse transformations where PdIV complexes are believed to act as key intermediates. It is clear that catalytic reaction manifolds involving PdIV intermediates offer new * Corresponding author. E-mail: ijsf1@york.ac.uk. Telephone: +44 (0)1904 434091. Fax: +44 (0)1904 432516. Chem. Rev. 2010, 110, 824–889 824

Emergence of palladium(IV) chemistry in synthesis and catalysis.

Pd-catalysed carbonylations: versatile technology for discovery and process chemists

Metal-catalyzed amidation

Deconstructive functionalizations involving scission of carbon-carbon double bonds are well established. In contrast, unstrained C(sp3)–C(sp3) bond cleavage and functionalization have less precedent. Here we report the use of deconstructive fluorination to access mono- and difluorinated amine derivatives by C(sp3)–C(sp3) bond cleavage in saturated nitrogen heterocycles such as piperidines and pyrrolidines. Silver-mediated ring-opening fluorination using Selectfluor highlights a strategy for cyclic amine functionalization and late-stage skeletal diversification, establishing cyclic amines as synthons for amino alkyl radicals and providing synthetic routes to valuable building blocks.

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Attila Takács

Papers

High-yielding synthesis of 1-isoindolinone derivatives via palladium-catalysed cycloaminocarbonylation

Homogeneous catalytic aminocarbonylation of nitrogen-containing iodo-heteroaromatics. Synthesis of N-substituted nicotinamide related compounds

Facile synthesis of 1,8-naphthalimides in palladium-catalysed aminocarbonylation of 1,8-diiodo-naphthalene

High-yielding synthesis of 2-arylacrylamides via homogeneous catalytic aminocarbonylation of α-iodostyrene and α,α′-diiodo-1,4-divinylbenzene

Synthesis of tetrahydrophthalazine and phthalamide (phthalimide) derivatives via palladium-catalysed carbonylation of iodoarenes