Seminar
Tuesday, October 9, 2018 - 12:00am
Graduate Student Nick Boekell will present
One-Pot, Multi-Component Catalysis: Powerful Library-Building Reactions
on October 9, 2018 at 4:10 PM in Neville Hall, Room 3
There are numerous challenges in the pursuit of obtaining complicated and multi-functionalized products using traditional synthetic methods. Among these challenges, minimizing product loss during intermediate isolation and avoiding side reactions have proven to be some of the most persistent even as new chemical technologies continue to emerge. In light of these challenges, one-pot, multi-component reactions are powerful methodological tools in multi-step organic syntheses. This seminar will discuss three such one-pot, multi-component reactions reported in the literature, each utilizing a different catalytic system to achieve unique chemical transformations. E. Anderson and coworkers describe a Pd(0)/Pd(II) catalyzed synthesis of disubstituted furans, a large class of notably versatile organic heterocycles.1,2 The method described in this work offers an alternative to the Paal-Knorr synthesis without the need for harsh reaction conditions or specialty equipment.3-6 V. Dong and coworkers present a bioinspired Rh(I) catalyzed synthesis of a variety of functionalized olefins from common primary and secondary alcohols.7 This breakthrough work provides a novel synthetic route for the production of olefinated feedstocks as well as simplified syntheses for complex natural products like (+)-yohimbenone. Van der Eycken and coworkers describe the Au(I), Ag(I) co-catalyzed synthesis of a large set of diversely functionalized alkaloids.7 The wide variety of highly-functionalized tricyclic alkaloids achieved in this work adds many potentially valuable natural product and pharmaceutical candidates to screening libraries.9,10 Overall, each of these methods not only provide useful syntheses of desirable products but also utilize one-pot, multi-component catalysis to neatly overcome the challenges inherent in traditional multi-step organic synthesis. 1) Arroniz, C.; Chaubet, G.; Anderson, E. A. Dual Oxidation State Tandem Catalysis in the Palladium-Catalyzed Isomerization of Alkynyl Epoxides to Furans. ACS Catal. 8, 8290–8295 (2018) 2) Peters, F. N. Industrial Uses of Furans. Ind. Eng. Chem. 31, 178–180 (1939) 3) Trofimov, A.; Chernyak, N; Gevorgyan, V. Dual Role of Alkynyl Halides in One-Step Synthesis of Alkynyl Epoxides. J. Am. Chem. Soc. 130, 13538–13539 (2008) 4) Burke, C. P.; Shi, Y. Enantioselective Epoxidation of Conjugated cis-Enynes by Chiral Dioxirane. J. Org. Chem. 72, 4093–4097 (2007) 5) Alexakis, A.; Marek, I.; Mangeney, P.; Normant, J. F. Diastereoselective syn or anti opening of propargylic epoxides. Synthesis of α-allenic alcohols. Tetrahedron 47, 1677–1696 (1991) 6) Gilchrist, T. L. Heterocyclic Chemistry; Pitman Publishing: London, 1985 7) Wu, X.; Cruz, F. A.; Lu, A.; Dong, V. M. Tandem Catalysis: Transforming Alcohols to Alkenes by Oxidative Dehydroxymethylation. J. Am. Chem. Soc. 140, 10126–10130 (2018) 8) He, Y.; Li, Z.; Robeyns, K.; Van Meervelt, L.; Van der Eycken, E. V. A Gold-Catalyzed Domino Cyclization Enabling Rapid Construction of Diverse Polyheterocyclic Frameworks. Angewandte Chemie International Edition 57, 272–276 (2018) 9) Davis, R. A. et al. Antimalarial Activity of Pyrroloiminoquinones from the Australian Marine Sponge Zyzzya sp. J. Med. Chem. 55, 5851–5858 (2012) 10) Feng, T. et al. Melotenine A, a Cytotoxic Monoterpenoid Indole Alkaloid from Melodinus tenuicaudatus. Org. Lett. 12, 968–971 (2010)