68692-65-9Relevant academic research and scientific papers
CuX2-mediated oxybromination/aminochlorination of unsaturated amides: Synthesis of iminolactones and lactams
Zhang, Zhi-Qiang,Liu, Feng
, p. 6690 - 6693 (2015)
We report herein a CuX2-mediated halocyclization of γ,δ-unsaturated amides for the synthesis of functionalized iminolactones and lactams respectively under mild reaction conditions. Mechanism studies indicated that N-attack cyclization was via a radical route while oxycyclization was via a nucleophilic attack on the activated CC bond.
Providing a New Aniline Bioisostere through the Photochemical Production of 1-Aminonorbornanes
Staveness, Daryl,Sodano, Taylor M.,Li, Kangjun,Burnham, Elizabeth A.,Jackson, Klarissa D.,Stephenson, Corey R.J.
supporting information, p. 215 - 226 (2019/01/21)
Recent years have witnessed an increasing focus on saturated substructures within drug development as a result of the pharmacokinetic and toxicological benefits correlated with higher saturation content. However, the synthetic challenges presented by densely functionalized saturated architectures generally prohibit their evaluation. The abundance of anilines within high-throughput screening libraries is demonstrative of these competing needs. Anilines are prone to adverse metabolic processing, commonly necessitating re-engineering of a given drug lead to ameliorate CYP450 inhibition and/or glutathione adduction issues, but the ease with which these systems are prepared outweighs the toxicity risks. This article contributes to the need for aniline bioisosteres through the development of a robust, photochemical methodology that supplies 1-aminonorbornanes, saturated bicyclic ring systems that offer similar spatial occupancy to anilines while improving metabolic stability. The chemistry provided herein details an efficient and flexible route toward architecturally distinctive 1-aminonorbornanes through the use of visible-light photoredox catalysis. The incorporation of readily diversifiable functional handles (e.g., -OH, -CO2Me, -NHBoc, -NHCbz) illustrates the potential utility of these 1-aminonorbornanes within drug-discovery programs. Additionally, these motifs offer improved metabolic stability relative to that of their aniline congeners (as demonstrated through microsomal stability assays and metabolite identification efforts), indicating applicability of 1-aminonorbornanes as aniline bioisosteres. This report describes the photochemical conversion of aminocyclopropanes into 1-aminonorbornanes via formal [3 + 2] cycloadditions initiated by homolytic fragmentation of amine radical cation intermediates. Aligning with the modern movement toward sp3-rich motifs in drug discovery, this strategy provides access to a diverse array of substitution patterns on this saturated carbocyclic framework while offering the robust functional-group tolerance (e.g., -OH, -NHBoc) necessary for further derivatization. Evaluating the metabolic stability of selected morpholine-based 1-aminonorbornanes demonstrated a low propensity for oxidative processing and no proclivity toward reactive metabolite formation, suggesting a potential bioisosteric role for 1-aminonorbornanes. Continuous-flow processing allowed for efficient operation on the gram scale, providing promise for translation to industrially relevant scales. This methodology only requires low loadings of a commercially available, visible-light-active photocatalyst and a simple salt; thus, it stays true to sustainability goals while readily delivering saturated building blocks that can reduce metabolic susceptibility within drug development programs.
Transition Metal Free Cycloamination of Prenyl Carbamates and Ureas Promoted by Aryldiazonium Salts
Abrams, Roman,Lefebvre, Quentin,Clayden, Jonathan
supporting information, p. 13587 - 13591 (2018/09/25)
Upon treatment with aryldiazonium salts, prenyl carbamates and ureas undergo redox-neutral azocycloamination. In general, N-aryl O-prenyl carbamates cyclize in a photocatalytic reaction with visible light and an organic dye. With electron-deficient diazonium salts, electronic matching with an electron-rich N-aryl substituent results in a reaction proceeding in the ground state, without either light or photocatalyst. Cyclic voltammetry suggests that this radical reaction is initiated by hydrogen-atom abstraction mediated by an aryl radical, followed by a radical addition cascade and proton-coupled hole propagation. The reaction proceeds at room temperature in short reaction times, and a range of functional groups is tolerated.
Copper-Catalyzed Amino Lactonization and Amino Oxygenation of Alkenes Using O-Benzoylhydroxylamines
Hemric, Brett N.,Shen, Kun,Wang, Qiu
supporting information, p. 5813 - 5816 (2016/06/09)
A copper-catalyzed amino lactonization of unsaturated carboxylic acids has been achieved as well as the analogous intermolecular three-component amino oxygenation of olefins. The transformation features mild conditions and a remarkably broad substrate sco
