An overview of the key routes to the best selling 5-membered ring heterocyclic pharmaceuticals

• Marcus Baumann,
• Ian R. Baxendale,
• Steven V. Ley and
• Nikzad Nikbin

Beilstein J. Org. Chem. 2011, 7, 442–495, doi:10.3762/bjoc.7.57

• compared to complex natural products, only a limited repertoire of synthetic transformations are utilised for their construction. Furthermore, many of the modern pioneering developments in organic synthesis including new highly selective and mild bond forming reactions such as metathesis and C–H activation

Photoinduced homolytic C–H activation in N-(4-homoadamantyl)phthalimide

• Nikola Cindro,
• Margareta Horvat,
• Kata Mlinarić-Majerski,
• Axel G. Griesbeck and
• Nikola Basarić

Beilstein J. Org. Chem. 2011, 7, 270–277, doi:10.3762/bjoc.7.36

• products [34]. Furthermore, suitably substituted phthalimides deactivate from the excited state by intramolecular H-abstractions to yield cyclization products, often benzazepinone derivatives [35][36][37]. Therefore, photoinduced homolytic C–H activation by phthalimide derivatives can, in principle, be

• -configuration. Conclusion N-(4-homoadamantyl)phthalimide (5) was synthesized and its photochemistry investigated. On excitation and population of the triplet state, 5 undergoes intramolecular homolytic C–H activation and gives products 6 and 7. The major product of the photochemical reaction is exo-alcohol 6

• ring closure to azetidinols and ring enlargement to azepinediones. High selectivity and high isolable yield of 6 in the photoreaction of 5 makes this photoinduced C–H activation useful in the synthesis of very complex derivatives with the homoadamantane skeleton with potential antiviral activity for

Backbone tuning in indenylidene–ruthenium complexes bearing an unsaturated N-heterocyclic carbene

• César A. Urbina-Blanco,
• Xavier Bantreil,
• Hervé Clavier,
• Alexandra M. Z. Slawin and
• Steven P. Nolan

Beilstein J. Org. Chem. 2010, 6, 1120–1126, doi:10.3762/bjoc.6.128

• via an observed C–H activation route [19]. These results encouraged us to explore the electronic influence of backbone substitution in unsaturated NHCs with ruthenium–indenylidene complexes. Indenylidene catalysts are rapidly becoming quite popular [20][21], due to the availability of ruthenium

Synthesis of dihydrophenanthridines by a sequence of Ugi-4CR and palladium- catalyzed intramolecular C-H functionalization

• Florence Bonnaterre,
• Michèle Bois-Choussy and
• Jieping Zhu

Beilstein J. Org. Chem. 2008, 4, No. 10, doi:10.3762/bjoc.4.10

• Scheme 1. The Ugi four-component reaction between an o-iodobenzaldehyde 2, an aniline 3, an isocyanide 4 and a carboxylic acid 5 should afford an α-acetamido-α-phenylacetamide 6, which upon palladium-catalyzed C-H activation process should provide dihydrophenanthridine 1 [15][16][17][18][19][20][21