Results 131 to 140 of about 169,803 (413)

An electrochemical gram-scale protocol for pyridylation of inert N-heterocycles with cyanopyridines

STAR Protocols, 2022
Summary: Here, we present a protocol to decyanopyridate inert N-heterocycles access to N-fused heterocycles via the mechanism of dual proton-coupled electron transfer (PCET).
Cong Niu, Jianjing Yang, Kelu Yan, Jiafang Xie, Wei Jiang, Bingwen Li, Jiangwei Wen   +6 more
doaj  

Lithiation of 4-membered heterocycles as useful strategy for the preparation of new molecular scaffolds: addressing the regioselectivity in azetidines and thietanes [PDF]

, 2013
Four-membered heterocycles (4-MH) with one or two heteroatoms are of great importance in medicinal chemistry and synthetic organic chemistry. This kind of scaffolds show peculiar structural features, related to the ring “puckering”, and biological ...
Carroccia, Laura, Degennaro, Leonardo, Falcicchio, Aurelia, Giovine, Arianna, Luisi, Renzo, Pisano, Luisa, Trinchera, Piera, Zenzola, Marina   +7 more
core  

Asymmetric synthesis of highly substituted spiro[2H‐pyrrole‐2,3‐succinimide] derivatives by copper‐catalyzed post‐Ugi reactions

Advanced Synthesis &Catalysis, Accepted Article.
Herein we present a novel one‐por methodology for the synthesis of enantioenriched 2H‐pyrrolespirosuccinimides by copper‐catalyzed reactions on Ugi adducts derived from enantiopure α‐alkylbenzyl amines through a chirality transfer process. We have proposed a mechanism supported by density functional theory (DFT) calculations, where a hydrogen radical ...
Maria Garcia Valverde, Javier Gómez-Ayuso, Israel Carreira-Barral, Roberto Quesada   +3 more
wiley   +1 more source

Polyoxometalate catalysts for the synthesis of N-heterocycles

Polyoxometalates
N-Heterocycle compounds are crucial scaffolds in natural products, synthetic molecules, agricultural chemicals, and pharmaceuticals. Hence, green catalytic systems for the synthesis of N-heterocycles have been widely researched in organic synthesis and ...
Qilong Hu, Ke Li, Xuejiao Chen, Yufeng Liu, Guoping Yang   +4 more
doaj   +1 more source

2-aminophenols containing electron-withdrawing groups from N-aryl hydroxylamines [PDF]

, 2010
Reaction of substituted N-aryl hydroxylamines with methanesulfonyl chloride, p-toluenesulfonyl chloride, or trifluoromethanesulfonic anhydride under basic conditions leads to the rearranged 2-aminophenols (45-94%).
Cooper, Anthony W. J., Porzelle, Achim, Tomkinson, Nicholas C.O., Woodrow, Michael D   +3 more
core   +1 more source

Synthesis of spirolactones from carbonyls via carboborylation of N‐sulfonylhydrazones with alkoxycarbonylalkylboronic acids

Advanced Synthesis &Catalysis, Accepted Article.
A straightforward synthesis of spirolactones from carbonyls via N‐tosylhydrazones is described. The process consist in the reaction between the N‐tosylhydrazone and ethoxycarbonylethylboronic acid or ethoxycarbonylpropylboronic acid, leading to spiro γ‐butyrolactones or δ‐valerolactones respectively. The transformation takes place by carboborylation of
Lucía López, Sara Filgueira, María-Paz Cabal, Alfonso Carlos Valdés-Gómez   +3 more
wiley   +1 more source

Experimental Simulation of Volatile Organic Contributions to Planetary Atmospheres and Surfaces [PDF]

, 2007
We present the results of a new simulation of the atmospheric entry heating experienced by extraterrestrial dust particles, quantifying their volatile loss into the early Earth atmosphere and characterising their organic volatile ...
Franchi, Ian, Gilmour, Iain, Morgan, Geraint, Pearson, Victoria, Turner, D. C., Wilson, Rebecca, Wright, Ian   +6 more
core  

Photochemical Preparation of (Aza‐)Indolines: Diastereoselective Synthesis and Polarity Reversal Strategy

Advanced Synthesis &Catalysis, Accepted Article.
Herein, we present the first light‐mediated, diastereoselective de novo synthesis for 2,3‐substituted indolines, a privileged scaffold in pharmaceuticals. The protocol was tested with various aryl and alkyl groups, maintaining high yields up to 85% across different substituents.
Julian Melder, Maxi Heldner, Julia Svetličić, Abdinasir Adow, Frank Rominger, Matthias Rudolph, Guenter Helmchen, A. Stephen K. Hashmi   +7 more
wiley   +1 more source

Reactivity and Stability of (Hetero)Benzylic Alkenes via the Wittig Olefination Reaction

Molecules
Wittig olefination at hetero-benzylic positions for electron-deficient and electron-rich heterocycles has been studied. The electronic effects of some commonly used protective groups associated with the N-heterocycles were also investigated for alkenes ...
Ajmir Khan, Mohammed G. Sarwar, Sher Ali
doaj   +1 more source

Aromaticities of Five Membered Heterocycles through Dimethyldihydropyrenes Probe by Magnetic and Geometric Criteria

Journal of Chemistry, 2015
Aromaticities of five membered heterocycles, containing up to three heteroatoms, are quantified through the dimethyldihydropyrene (DHP) probe. Bond fixation caused by the fusion of heterocycles to the dimethyldihydropyrene nucleus (DHPN) was measured by ...
Maria, Khurshid Ayub
doaj   +1 more source