scholarly journals Gold-Catalyzed Alkynes Ring-Opening Addition Reaction with Dioxane

2014 ◽  
Vol 34 (9) ◽  
pp. 1857 ◽  
Author(s):  
Dong Yan ◽  
Chao Wu ◽  
Weiguo Yi
Keyword(s):  
Ring Opening ◽  
Addition Reaction

Metal Doped-C3N4/Fe2O4: Efficient and Versatile Heterogenous Catalysts for Organic Transformations

2019 ◽  
Vol 23 (12) ◽  
pp. 1284-1306
Author(s):  
Vijai K. Rai ◽  
Fooleswar Verma ◽  
Suhasini Mahata ◽  
Smita R. Bhardiya ◽  
Manorama Singh ◽  
...  
Keyword(s):  
Ring Opening ◽  
Carbon Nitride ◽  
Addition Reaction ◽  
High Surface ◽  
Graphitic Carbon ◽  
Graphitic Carbon Nitride ◽  
Organic Transformations ◽  
Reduction Reactions ◽  
Activation Reaction ◽  
Metal Doped

The polymeric graphitic carbon nitride (g-C3N4) has been one of the interesting earth abundant elements. Though g-C3N4 finds application as a photocatalyst, its photocatalytic behaviour is limited because of low efficiency, mainly due to rapid charge recombination. To overcome this problem, several strategies have been developed including doping of metal/non-metal in the cavity of g-C3N4. Moreover, the CoFe2O4 NPs have been used in many organic transformations because of its high surface area and easy separation due to its magnetic nature. This review describes the role of cobalt ferrite as magnetic nanoparticles and metal-doped carbon nitride as efficient heterogeneous catalysts for new carbon-carbon and carbon-hetero atom bond formation followed by heterocyclization. Reactions which involved new catalysts for selective activation of readily available substrates has been reported herein. Since nanoparticles enhance the reactivity of catalyst due to higher catalytic area, they have been employed in various reactions such as addition reaction, C-H activation reaction, coupling reaction, cyclo-addition reaction, multi-component reaction, ring-opening reaction, oxidation reaction and reduction reactions etc. The driving force for choosing this topic is based-on huge number of good publications including different types of spinels/metal doped-/graphitic carbon nitride reported in the literature and due to interest of synthetic community in recent years. This review certainly will represent the present status in organic transformation and for exploring further their catalytic efficiency to new organic transformations involving C-H activation reaction through coupling, cyclo-addition, multi-component, ring-opening, oxidation and reduction reactions.

Second-order nonlinear optical hyperbranched polymers via facile ring-opening addition reaction of azetidine-2,4-dione

2007 ◽  
Vol 43 (9) ◽  
pp. 3988-3996 ◽  
Author(s):  
Huey-Ling Chang ◽  
Tsung-Yi Chao ◽  
Chih-Chiang Yang ◽  
Shenghong A. Dai ◽  
Ru-Jong Jeng
Keyword(s):  
Ring Opening ◽  
Nonlinear Optical ◽  
Addition Reaction ◽  
Hyperbranched Polymers ◽  
Second Order

scholarly journals Enantioselective Conjugate Addition of Catalytically Generated Zinc Homoenolate

2021 ◽  
Author(s):  
Yoshiya Sekiguchi ◽  
Naohiko Yoshikai
Keyword(s):  
Amino Alcohol ◽  
Ring Opening ◽  
Addition Reaction ◽  
Aldol Condensation ◽  
Nonlinear Effects ◽  
Conjugate Addition ◽  
Unsaturated Ketone ◽  
Lower Reactivity

<div> <div> <div> <p>We report herein an enantioselective conjugate addition reaction of a zinc homoenolate, catalytically generated via ring opening of a cyclopropanol, to an α,β-unsaturated ketone. The reaction is promoted by a zinc aminoalkoxide catalyst generated from Et2Zn and a chiral β-amino alcohol to afford 1,6- diketones, which undergo, upon heating, intramolecular aldol condensation to furnish highly substituted cyclopentene derivatives with good to high enantioselectivities. The reaction has proved applicable to various 1-substituted cyclopropanols as well as chalcones and related enones. The chiral amino alcohol has proved to enable ligand-accelerated catalysis of the homoenolate generation and its conjugate addition. Positive nonlinear effects and lower reactivity of a racemic catalyst have been observed, which can be attributed to a stable and inactive heterochiral zinc aminoalkoxide dimer. </p> </div> </div> </div>

Photoredox Catalyzed Ring-Opening Addition Reaction Between Benzyl Bromides and Cyclic Ethers

Synthesis ◽  
2021 ◽  
Author(s):  
Cuiwen Kuang ◽  
Chuanfa Ni ◽  
Yucheng Gu ◽  
Jinbo Hu
Keyword(s):  
Ring Opening ◽  
Addition Reaction ◽  
Benzyl Bromide ◽  
Addition Product ◽  
Cyclic Ether ◽  
Cyclic Ethers ◽  
Single Electron Transfer ◽  
Nucleophilic Reaction ◽  
Reaction Proceeds ◽  
Bromide Ion

A novel nucleophilic reaction between cyclic ethers and benzyl bromides is achieved under photoredox catalysis. The reaction proceeds through a single electron transfer (SET) pathway rather than a common SN2 mechanism. By two steps of reduction and oxidation, a benzyl bromide heterolyzes to give a carbocation and bromide ion under mild conditions, and then a cyclic ether captures both the carbocation and bromide ion to afford the addition product.

Synthesis and characterization of novel barbwire-like graft polymers poly(ethylene oxide)-g-poly(ε-caprolactone)4 by the ‘grafting from’ strategy

2015 ◽  
Vol 6 (3) ◽  
pp. 466-475 ◽  
Author(s):  
Xinyi Liang ◽  
Yujie Liu ◽  
Jian Huang ◽  
Liuhe Wei ◽  
Guowei Wang
Keyword(s):  
Ethylene Oxide ◽  
Ring Opening ◽  
Addition Reaction ◽  
Ring Opening Polymerization ◽  
Synthesis And Characterization ◽  
Graft Polymers ◽  
Poly Ethylene Oxide ◽  
Poly Ethylene ◽  
Grafting From

Novel barbwire-like graft polymers PEO-g-PCL4 were synthesized by combination of ring opening polymerization (ROP) and Glaser coupling with thiol–yne addition reaction via the “grafting from” strategy.

scholarly journals Excellent UV-Absorbing Cotton Fabric with High Durability and Hydrophobicity Based on Surface-Initiated ATRP of Polymerizable Organic UV-Absorber

2021 ◽  
Author(s):  
Saixiang Hua ◽  
Huichao Zhu ◽  
Xiao Wang ◽  
Mingyuan Wu ◽  
Qingyun Wu ◽  
...  
Keyword(s):  
Cotton Fabric ◽  
Ring Opening ◽  
Glycidyl Methacrylate ◽  
Addition Reaction ◽  
Protection Factor ◽  
Hydrophobic Property ◽  
Water Contact ◽  
Uv Absorber ◽  
High Durability ◽  
Absorption Performance

Abstract Ultraviolet (UV) protective cotton fabric is a convenient and reliable way to protect human body from sunlight. Herein, a polymerizable organic UV-absorber, 2-hydroxy-4-(3-methacryloxy-2-hydroxylpropoxy) benzophenone (BPMA) was prepared from the ring-opening addition reaction of 2,4-dihydroxybenzophenone (UV-0) with glycidyl methacrylate (GMA). The initiators tethered cotton fabric (CF-Br) were prepared by the immobilization of α-bromoisobutyryl groups. PBPMA grafted cotton fabric (CF-g-PBPMA) was fabricated via surface-initiated atom transfer radical polymerization (SI-ATRP). The experimental results indicated that BPMA was successfully synthesized, and PBPMA chains were successfully grafted from CF-Br. Importantly, CF-g-PBPMA exhibited excellent UV absorption performance, hydrophobic ability and outstanding durability. Compared with the UV protection factor (UPF) of the original cotton fabric (3.5), the UPF of CF-g-PBPMA achieved 241.5, which was far beyond the excellent protection UPF rating (50+) and was up to 69-fold higher than that of original cotton fabric. Compared with the water contact angle (WCA) of the original cotton fabric of 46°, the WCA of CF-g-PBPMA reached 140°, showing excellent hydrophobic property. In addition, after five washing cycles, CF-g-PBPMA showed an outstanding durability with the WCA and UPF achieving 131° and 226.9, respectively.

scholarly journals Copper-Catalyzed Ring-Opening Reactions of Alkyl Aziridines with B2pin2: Experimental and Computational Studies

Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7399
Author(s):  
Lucilla Favero ◽  
Andrea Menichetti ◽  
Cosimo Boldrini ◽  
Lucrezia Margherita Comparini ◽  
Valeria Di Bussolo ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Nucleophilic Addition ◽  
Ring Opening ◽  
Addition Reaction ◽  
Computational Studies ◽  
Reaction Conditions ◽  
Ring Opening Reactions ◽  
Computational Data ◽  
Nucleophilic Addition Reaction ◽  
Direct Preparation

The possibility to form new C–B bonds with aziridines using diboron derivatives continues to be a particularly challenging field in view of the direct preparation of functionalized β-aminoboronates, which are important compounds in drug discovery, being a bioisostere of β-aminoacids. We now report experimental and computational data that allows the individuation of the structural requisites and of reaction conditions necessary to open alkyl aziridines using bis(pinacolate)diboron (B2pin2) in a regioselective nucleophilic addition reaction under copper catalysis.

Sign in / Sign up

Export Citation Format

Share Document