Pyrrole Synthesis through Cu-Catalyzed Cascade [3+2] Spiroannulation/Aromatization of Oximes with Azadienes

2021 ◽  
Author(s):  
Jing Lin ◽  
Ting-Yu Zheng ◽  
Neng-Quan Fan ◽  
Pu Zhang ◽  
Kun Jiang ◽  
...  
Keyword(s):  
Present Approach ◽  
Synthetic Method ◽  
Substituted Pyrroles

We have disclosed a new synthetic method for the rapid assembly of poly-substituted pyrroles with readily accessible oximes and azadienes as the starting materials. The present approach generates an array...

Direct Cyclization of Alkenyl Thioester via Transition Metal‐hydrogen Atom Transfer/radical‐polar Crossover Mechanism

2019 ◽  
Author(s):  
Shiori Date ◽  
Kensei Hamasaki ◽  
Karen Sunagawa ◽  
Hiroki Koyama ◽  
Chikayoshi Sebe ◽  
...  
Keyword(s):  
Natural Products ◽  
Hydrogen Atom ◽  
Transition Metal ◽  
Hydrogen Atom Transfer ◽  
Synthetic Method ◽  
Atom Transfer ◽  
Reaction Conditions ◽  
Hydride Hydrogen ◽  
Sulfur Heterocycles ◽  
One Step

<div>We report here a catalytic, Markovnikov selective, and scalable synthetic method for the synthesis of saturated sulfur heterocycles, which are found in the structures of pharmaceuticals and natural products, in one step from an alkenyl thioester. Unlike a potentially labile alkenyl thiol, an alkenyl thioester is stable and easy to prepare. The powerful Co catalysis via a cobalt hydride hydrogen atom transfer and radical-polar crossover mechanism enabled simultaneous cyclization and deprotection. The substrate scope was expanded by the extensive optimization of the reaction conditions and tuning of the thioester unit.</div>

Efficient CDI/CH3SO3H -Catalyzed, Microwave-Assisted Synthesis of 2-Substituted Benzothiazoles

2018 ◽  
Vol 16 (1) ◽  
pp. 34-39
Author(s):  
Yao-Wei Li ◽  
Pei-Ming Zhang ◽  
Rui Li ◽  
Yan Bai ◽  
Yu Yu ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Carboxylic Acids ◽  
1H Nmr ◽  
Good Yield ◽  
Microwave Assisted Synthesis ◽  
Synthetic Method ◽  
Benzothiazole Derivatives ◽  
Microwave Assisted ◽  
Highly Effective

CDI combined with CH3SO3H was found to be highly effective for the cyclization of 2-aminothiophenol derivatives with carboxylic acids under MW condition. Fourteen benzothiazole derivatives were synthesized in good yield and their structures were characterized by 1H-NMR, 13CNMR, IR and mass spectrometry. This simple, rapid synthetic method is believed to provide a useful process for the synthesis of 2-substituted benzothiazole compounds.

4-Hydroxy Pyridinium Triflate@SiO2 Nanoparticles as a Novel Efficient Catalyst for Fries Rearrangement of Aryl Esters with High Selectivity

2020 ◽  
Vol 17 (8) ◽  
pp. 654-660
Author(s):  
Shermineh Sadat Ghalehbandi ◽  
Dadkhoda Ghazanfari ◽  
Sayed Ali Ahmadi ◽  
Enayatollah Sheikhhosseini
Keyword(s):  
High Selectivity ◽  
Sio2 Nanoparticles ◽  
High Yield ◽  
Synthetic Method ◽  
Functionalized Silica ◽  
Efficient Catalyst ◽  
Fries Rearrangement ◽  
Free Condition ◽  
Solvent Free Condition ◽  
Work Up

Introduction: We developed a simple, fast and new method for the Fries rearrangement of aryl esters. Materials and Methods: 4-Hydroxy pyridinium triflate functionalized silica is a very efficient, reusable and economically available catalyst for the Fries rearrangement in solvent-free condition and under microwave irradiation. Results and Discussion: Also, a notable selectivity was observed in the presence of 4-hydroxy pyridinium triflate functionalized silica. Conclusion: Selectivity, shorter reaction time, high yield, and easy work-up are advantages of this synthetic method.

Why Phenomenology?

2018 ◽  
Author(s):  
George Pattison
Keyword(s):  
Twentieth Century ◽  
Subject Matter ◽  
Alternative Model ◽  
Phenomenological Approach ◽  
Human Existence ◽  
Present Approach ◽  
The Self ◽  
Existence Of God ◽  
Pure Intuition ◽  
The Way

This chapter sets out the rationale for adopting a phenomenological approach to the devout life literature. Distinguishing the present approach from versions of the phenomenology of religion dominant in mid-twentieth-century approaches to religion, an alternative model is found in Heidegger’s early lectures on Paul. These illustrate that alongside its striving to achieve a maximally pure intuition of its subject matter, phenomenology will also be necessarily interpretative and existential. Although phenomenology is limited to what shows itself and therefore cannot pass judgement on the existence of God, it can deal with God insofar as God appears within the activity and passivity of human existence. From Hegel onward, it has also shown itself open to seeing the self as twofold and thus more than a simple subjective agent, opening the way to an understanding of the self as essentially spiritual.

Electroreductive Intramolecular Coupling of Aromatic β- and γ-Imino Esters:  A New Synthetic Method forN-Alkoxycarbonyl-2-aryl-3-ones andcis-2-Aryl-3-ols of Pyrrolidines and Piperidines

2004 ◽  
Vol 69 (22) ◽  
pp. 7710-7719 ◽  
Author(s):  
Naoki Kise ◽  
Kengo Ohya ◽  
Kie Arimoto ◽  
Yutaka Yamashita ◽  
Yuuki Hirano ◽  
...  
Keyword(s):  
Synthetic Method ◽  
Imino Esters

P-51: Preparation of (Y,Gd)BO[sub 3]:Eu[sup 3+] Phosphor with High Luminescent Efficiency by New Synthetic Method

2001 ◽  
Vol 32 (1) ◽  
pp. 742
Author(s):  
Dong-Kuk Kim ◽  
Seon-Mi Yoon ◽  
Cha-Joo Park ◽  
Song-Ho Byeon ◽  
Jung-Chul Park ◽  
...  
Keyword(s):  
Synthetic Method

Self-templated formation of hierarchically yolk-shell-structured ZnS/NC dodecahedra with superior lithium storage properties

Nanoscale ◽  
2021 ◽  
Author(s):  
Ping Wang ◽  
Aihua Yuan ◽  
Zhitao Wang ◽  
Xiao Ping Shen ◽  
Hantao Chen ◽  
...  
Keyword(s):  
Synthetic Method ◽  
Zeolitic Imidazolate Frameworks ◽  
Lithium Storage ◽  
Storage Properties

The hierarchical ZnS/NC dodecahedra are successfully constructed via a two-step synthetic method combining a sulfidation process and subsequent carbonization treatment, benefiting from the inherit merits of zeolitic imidazolate frameworks as...

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