Pd-Catalyzed Oxidative Functionalization of Alkenes, Arenes, and 1,3-Dienes Using Molecular Oxygen as the Terminal Oxidant
Conclusions and Perspectives [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - January 19, 2024 Category: Chemistry Authors: Tabaru, Kazuki Obora, Yasushi Tags: account Source Type: research
Adventures in CH-Arylation Chemistry
Synlett DOI: 10.1055/s-0042-1751540 The present article provides a personalized account on CH-arylation reactions employed for the synthesis of heterocycles. The presence of a nitro group allowed for direct and regioselective CH-arylations of pyrazoles, imidazoles, indoles and a variety of purine analogues. Direct CH-arylations without the presence of an activating nitro-group were employed for inter- and intramolecular reactions of purine derivatives, which allowed for the synthesis of a great variety of polycyclic systems. Domino C–N coupling / hydroamination / CH-activation reactions of diarylacetylenes with anilines ...
Source: Synlett - January 19, 2024 Category: Chemistry Authors: Langer, Peter Tags: account Source Type: research
Chemoselective Vicinal Dichlorination of Alkenes by Iron Ligand-to-Metal Charge-Transfer Catalysis
We report the photocatalytic functionalization of terminal alkenes to vicinal dichlorides by using visible light and FeCl3 as a catalyst, LiCl as a chloride source, and air as an oxidant. The transformation is proposed to be initiated by ligand-to-metal charge-transfer bond homolysis of a Fe–Cl bond, giving a highly reactive chloride radical able to initiate the functionalization of olefins. The process shows high chemoselectivity and broad functional-group tolerance with yields of up to 94% under mild conditions. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table ...
Source: Synlett - January 18, 2024 Category: Chemistry Authors: Stahl, Jessica Reiter, Thilo K önig, Burkhard Tags: letter Source Type: research
Ligand-Free Copper(I) Chloride Catalyzed N-Arylation of 1,2,4-Triazole with Aryl Bromides
Synlett DOI: 10.1055/a-2229-1887 An efficient protocol was developed for the N-arylation of 1,2,4-triazole by using substituted aryl bromides catalyzed by CuCl under ligand-free conditions. This method afforded the products in good to excellent yields (up to 88%) under the optimized conditions. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - January 18, 2024 Category: Chemistry Authors: Ang, WeiZhi Low, Chloe Kah-Yee Teo, Yong-Chua Tags: letter Source Type: research
Regioselective Formation of Pyridines by Cycloaddition/Cycloreversion of 1,4-Oxazinone Precursors with Bisalkyne Substrates
This study explores the merged cycloaddition/cycloreversion of a 1,4-oxazinone substrate and conjugated bisalkyne precursors. Good regioselectivity in the Diels–Alder operation is observed and pyridines bearing 3-alkynyl functionality are afforded following cycloreversion and extrusion of CO2. Examples with both symmetric and nonsymmetric bisalkyne substrates are included. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - January 18, 2024 Category: Chemistry Authors: Andres, Graydon J. Anderson, Seth E. Kinsey, Adrianne M. Scheerer, Jonathan R. Tags: letter Source Type: research
Topological Bistability of the π-System in a Helicene Carbon Nanohoop
Synlett DOI: 10.1055/a-2223-7245 Molecules with a π-system that can be mapped onto a Möbius strip may display Möbius aromaticity. Such molecules are difficult to synthesize because they have a twisted structure. Recently, we combined chiral [6]helicene and fluorescent [7]cycloparaphenylene, and synthesized the first helicene para-phenylene ([6,7]HPP) carbon nanohoop. We have demonstrated that this design strategy ultimately provides a Möbius topology of the molecular π-electron system and, therefore, offers the potential to study Möbius aromaticity experimentally. In addition, the synthesized nanohoop exists as a mix...
Source: Synlett - January 17, 2024 Category: Chemistry Authors: Malin čík, Juraj Šolomek, Tomáš Tags: synpacts Source Type: research
yTopological Bistability of the π-System in a Helicene Carbon Nanohoop
Synlett DOI: 10.1055/a-2223-7245 Molecules with a π-system that can be mapped onto a Möbius strip may display Möbius aromaticity. Such molecules are difficult to synthesize because they have a twisted structure. Recently, we combined chiral [6]helicene and fluorescent [7]cycloparaphenylene, and synthesized the first helicene para-phenylene ([6,7]HPP) carbon nanohoop. We have demonstrated that this design strategy ultimately provides a Möbius topology of the molecular π-electron system and, therefore, offers the potential to study Möbius aromaticity experimentally. In addition, the synthesized nanohoop exists as a mix...
Source: Synlett - January 17, 2024 Category: Chemistry Authors: Malin čík, Juraj Šolomek, Tomáš Tags: synpacts Source Type: research
Synthesis of Biomimetic Thioesters for Studies of Ketoreductase Domains from the Biosynthesis of Cytotoxic Polyketides
Synlett DOI: 10.1055/a-2216-4521 The synthesis of biomimetic thioesters for enzymatic studies of ketoreductase (KR) domains from polyketide synthases is described. A TBS-protected dihydroxyalkene fragment was synthesised by a sequence involving a Nagao acetate aldol reaction, a Mukaiyama propionate aldol reaction, and a methylene Wittig olefination. Fragment coupling to N-acetylcysteamine (SNAC) (E)-3-hydroxyhex-4-enethioates by an olefin cross-metathesis (OCM) and subsequent deprotection gave the potential KR product stereoisomers. An analogous OCM with a SNAC (E)-3-ketohex-4-enethioate did not give the desired KR precurs...
Source: Synlett - January 17, 2024 Category: Chemistry Authors: Derra, Sebastian Hoffmann, Julian Hahn, Frank Tags: letter Source Type: research
Method Development and Syntheses Examples of Isotopically Labeled Compounds to Foster Operational Excellence in Pharma Industry
Conclusion [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - January 17, 2024 Category: Chemistry Authors: Sib, Anna Derdau, Volker Tags: account Source Type: research
Acetal Substitution Reactions: Stereoelectronic Effects, Conformational Analysis, Reactivity vs Selectivity, and Neighboring-Group Participation
Conclusion [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - January 16, 2024 Category: Chemistry Authors: Chun, Yuge Luu, Khoi B. Woerpel, K. A. Tags: account Source Type: research
The Cyanopyridine –Aminothiol Click Reaction: Expanding Horizons in Chemical Biology
Conclusion [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - January 15, 2024 Category: Chemistry Authors: Nitsche, Christoph Tags: synpacts Source Type: research
Systematic Strategy for the Development of Glycosyltransferase Inhibitors: Diversity-Oriented Synthesis of FUT8 Inhibitors
This study proposes an efficient strategy to accelerate the structural optimization of middle molecules. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - January 15, 2024 Category: Chemistry Authors: Manabe, Yoshiyuki Hizume, Koki Takakura, Yohei Takamatsu, Shinji Miyoshi, Eiji Kamada, Yoshihiro Hurtado-Guerrero, Ram ón Fukase, Koichi Tags: letter Source Type: research
Stereoselective Synthesis of Volicitin and 9-D
1-Volicitin
Synlett DOI: 10.1055/s-0042-1751547 The synthesis of volicitin involved the condensation of l-(+)-glutamine with 17(S)-hydroxylinolenoic acid, derived from a Wittig reaction between the C10–C18 phosphonium salt and the C1–C9 aldehyde. The phosphonium salt was prepared through the alkynylation of a (Z)-allylic phosphate with an alkyne derived from (2S)-but-3-yn-2-ol. The deuterated aldehyde was derived with a 96% deuteration ratio by reduction of the C1–C9 methyl ester with NaBD4, followed by oxidation. Subsequently, 9-D
1-volicitin was synthesized from the monodeuterated aldehyde by using the Wittig reaction an...
Source: Synlett - January 15, 2024 Category: Chemistry Authors: Mamada, Shunki Niwa, Kosuke Toyoshima, Shoya Seto, Yoshiya Ogawa, Narihito Tags: letter Source Type: research
Radiosynthesis of α-[18F]Fluoroamides with [18F]AgF
Synlett DOI: 10.1055/s-0041-1738458 A silver-promoted nucleophilic radiofluorination of α-bromoamides has been developed for the radiosynthesis of α-[18F]fluoroamides. The reaction conditions are straightforward and compatible with primary, secondary, and tertiary α-bromoamides. Furthermore, the methodology has been successfully applied to the synthesis of bioactive radiotracers with good radiochemical conversion (RCC) and radiochemical yield (RCY). [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents | Abstract | Full text (Source: Synlett)
Source: Synlett - January 15, 2024 Category: Chemistry Authors: Gong, Kehao Yin, Zhengxu Song, Pengfei Xu, Bo Han, Junbin Tags: letter Source Type: research
Nickel-Catalyzed Synthesis of Benzylamines from (Hetero)aryl Halides and Glycine-Derived N-Hydroxyphthalimide Esters
Synlett DOI: 10.1055/s-0043-1763656 A nickel-catalyzed aminomethylation of aryl or heteroaryl iodides or bromides for the preparation of protected primary benzylamines is reported. This cross-electrophile reductive protocol engages carbamate-protected, glycine-derived N-hydroxyphthalimide (NHP) esters in an efficient decarboxylative cross-coupling in only two hours. The catalyst and NHP ester reagents are commercially available or can be synthesized in one step on a decagram scale with no chromatography. [...] Georg Thieme Verlag KG Rüdigerstraße 14, 70469 Stuttgart, GermanyArticle in Thieme eJournals: Table of contents...
Source: Synlett - January 12, 2024 Category: Chemistry Authors: Choi, Eun Seo Rousseaux, Sophie A. L. Huestis, Malcolm P. Tags: letter Source Type: research
