Results 111 to 120 of about 23,082 (272)

Metal-free intermolecular formal cycloadditions enable an orthogonal access to nitrogen heterocycles

Nature Communications, 2016
Nitrogen containing heterocycles play key roles as both bioactive compounds and synthetic building blocks in organic chemistry. Here, the authors report the synthesis of a range of heterocyclic structures via metal free cycloadditions and provide ...
Lan-Gui Xie, Supaporn Niyomchon, Antonio J. Mota, Leticia González, Nuno Maulide   +4 more
doaj   +1 more source

Catalysed low temperature H-2 release from nitrogen heterocycles

, 2006
In an experimental and computational study, nitrogen- and oxygen-containing heterocycles were compared with carbocycles as liquid substrates for hydrogen release with heterogeneous catalysts. Heteroatom substitution, particularly by nitrogen, favours low
Poyatos, Macarena, Luo, Yi,, Moores, Audrey, Crabtree, Robert H.   +3 more
core   +1 more source

Metal‐Free Active Template: A Straightforward Route to 4‐Aminopyridinium‐Based Rotaxane Molecular Shuttles

Angewandte Chemie, EarlyView.
Leigh's metal‐free active template‐based SNAr of an amine on halogenopyridiniums, in the presence of a crown ether, successfully afforded 4‐aminopyridinium‐containing rotaxanes. Further molecular machinery was carried out by deprotonation‐then‐carbamoylation of the conjugated amino moiety.
Ivaylo Stoyanov, Arie van der Lee, Frédéric Coutrot   +2 more
wiley   +2 more sources

Radiation-driven Destruction of N-heterocycles in the Presence and Absence of Water Ice

The Astrophysical Journal
Simple N -heterocycles are expected to be an abundant class of molecules within the interstellar medium, and increasingly complex heterocycles (e.g., nucleobases) have been detected within meteoritic organic material and in samples returned from the ...
Patrick D. Tribbett, Yukiko Y. Yarnall, Perry A. Gerakines, Reggie L. Hudson, Christopher K. Materese   +4 more
doaj   +1 more source

Palladium-Catalyzed Modular Synthesis of Substituted Piperazines and Related Nitrogen Heterocycles

, 2016
We report here a novel method for the modular synthesis of highly substituted piperazines and related bis-nitrogen heterocycles via a palladium-catalyzed cyclization reaction.
Thomas D. Montgomery (1325580), Viresh H. Rawal (1323897)   +1 more
core   +1 more source

Formal pyridine meta-azidation and its application for the synthesis of diazepines, ring-fused δ-carbolines and 1,2,3-triazolylpyridines

Nature Communications
The nitrogen atom serves as an important structural element in pharmacologic studies, highlighting the critical role of nitrogen-containing heterocycles in drug discovery.
Shu-Min Guo, Pengwei Xu, Constantin G. Daniliuc, Armido Studer   +3 more
doaj   +1 more source

An Enantioselective Alkene Aminoarylation to Form Chiral Indolines via Electrostatically‐Directed Palladium Catalysis

Angewandte Chemie, EarlyView.
Enantioselective aminoarylation of ortho‐allyl anilines is achieved under mild conditions. Key to success is the electrostatically‐directed nature of the key aminopalladation step, achieved by using the sulfonated chiral ligand sSPhos on palladium. A detailed study of electronic trends allows tuning of the sulfonamide protecting group to enable good ...
Max Kadarauch, Paul T. Jirsch, H. Erik Diepers, Hamzah Sharif, Robert J. Phipps   +4 more
wiley   +2 more sources

Diastereoselective Alkylation of Activated Nitrogen Heterocycles with Alkenyl Boronate Complexes. [PDF]

Angew Chem Int Ed Engl, 2023
McGettigan JE, Ready JM.
europepmc   +1 more source

Heterocycles. CI. Syntheses and Isomerizations of Some Allylthio Nitrogen Heterocycles

, 1973
Allylthio nitrogen heterocycles were isomerized under the influence of base into the corresponding propenylthio analogs. Subsequently, isomerization of the resultant cis-propenylthio compounds afforded the trans-isomers.
Stanovnik, B., B. Stanovnik, Kočevar, M., M. Kočevar, Tišler, M., M. Tišler   +5 more
core  

2‐Azaazulenium Hemicyanine Dyes for NIR‐II Multimodal Imaging and Combined Phototherapy

Angewandte Chemie, EarlyView.
A strategically engineered class of 2‐azaazulenium hemicyanines is developed, featuring bright fluorescence in the second near‐infrared (NIR‐II) window and multifunctional performance. SWJT‐OCH3 shows type I/II reactive oxygen species (ROS) generation and excellent photothermal activity.
Min Peng, Bing‐Ya Wang, Hai Xu, Qiang Wang, Rong‐Dan Xiao, Rui Tan, Yu Peng, Ya‐Wen Wang, Juyoung Yoon   +8 more
wiley   +2 more sources