Skeletal Rearrangement during Rhodium-Promoted Ring Opening of 1,2-Diphenyl-3-vinyl-1-cyclopropene. Preparation and Characterization of 1,2- and 2,3-Diphenyl-3,4-pentadienediyl Rhodium Complexes and Their Ring Closure to a 1,2-Diphenylcyclopentadienyl Complex

1999 ◽  
Vol 18 (15) ◽  
pp. 2766-2772 ◽  
Author(s):  
Russell P. Hughes ◽  
Hernando A. Trujillo ◽  
James W. Egan ◽  
Arnold L. Rheingold
Keyword(s):  
Ring Opening ◽  
Ring Closure ◽  
Rhodium Complexes ◽  
Skeletal Rearrangement

scholarly journals Synthesis and characterization of different soybean oil-based polyols with fatty alcohol and aromatic alcohol

e-Polymers ◽  
2021 ◽  
Vol 21 (1) ◽  
pp. 491-499
Author(s):  
Fukai Yang ◽  
Hao Yu ◽  
Yuyuan Deng ◽  
Xinyu Xu
Keyword(s):  
Molecular Weight ◽  
Soybean Oil ◽  
Retention Time ◽  
Ring Opening ◽  
Isoamyl Alcohol ◽  
Synthesis And Characterization ◽  
Intermolecular Force ◽  
H Nmr ◽  
Epoxy Groups

Abstract In this article, five kinds of soybean oil-based polyols (polyol-E, polyol-P, polyol-I, polyol-B, and polyol-M) were prepared by ring-opening the epoxy groups in epoxidized soybean oil (ESO) with ethyl alcohol, 1-pentanol, isoamyl alcohol, p-tert-butylphenol, and 4-methoxyphenol in the presence of tetrafluoroboric acid as the catalyst. The SOPs were characterized by FTIR, 1H NMR, GPC, viscosity, and hydroxyl numbers. Compared with ESO, the retention time of SOPs is shortened, indicating that the molecular weight of SOPs is increased. The structure of different monomers can significantly affect the hydroxyl numbers of SOPs. Due to the large steric hindrance of isoamyl alcohol, p-hydroxyanisole, and p-tert-butylphenol, SOPs prepared by these three monomers often undergo further dehydration to ether reactions, which consumes the hydroxyl of polyols, thus forming dimers and multimers; therefore, the hydroxyl numbers are much lower than polyol-E and polyol-P. The viscosity of polyol-E and polyol-P is much lower than that of polyol-I, polyol-B, and polyol-M. A longer distance between the molecules and the smaller intermolecular force makes the SOPs dehydrate to ether again. This generates dimer or polymers and makes the viscosity of these SOPs larger, and the molecular weight greatly increases.

scholarly journals Synthesis and Characterization of Polyphosphazenes Modified with Hydroxyethyl Methacrylate and Lactic Acid

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Evelyn Carolina Martínez Ceballos ◽  
Ricardo Vera Graziano ◽  
Gonzalo Martínez Barrera ◽  
Oscar Olea Mejía
Keyword(s):  
Lactic Acid ◽  
Ring Opening ◽  
Room Temperature ◽  
Block Structure ◽  
Ring Opening Polymerization ◽  
Synthesis And Characterization ◽  
Poly Lactic Acid ◽  
Hydroxyethyl Methacrylate ◽  
H Nmr

Poly(dichlorophosphazene) was prepared by melt ring-opening polymerization of the hexachlorocyclotriphosphazene. Poly[bis(2-hydroxyethyl-methacrylate)-phosphazene] and poly[(2-hydroxyethyl-methacrylate)-graft-poly(lactic-acid)-phosphazene] were obtained by nucleophilic condensation reactions at different concentrations of the substituents. The properties of the synthesized copolymers were assessed by FTIR,1H-NMR and31P-NMR, thermal analysis (DSC-TGA), and electron microscopy (SEM). The copolymers have a block structure and show twoTg's below room temperature. They are stable up to a temperature of 100°C. The type of the substituents attached to the PZ backbone determines the morphology of the polymers.

Synthesis and characterization of Mannich base monophenolate lanthanide complexes and their application in ring-opening polymerization of ε-caprolactone

2016 ◽  
Vol 30 (6) ◽  
pp. 458-464 ◽  
Author(s):  
Ling Peng ◽  
Jing Zhao ◽  
Li-Jun Wang ◽  
Xian Tao ◽  
Yu-Long Wang ◽  
...  
Keyword(s):  
Ring Opening ◽  
Lanthanide Complexes ◽  
Mannich Base ◽  
Ring Opening Polymerization ◽  
Synthesis And Characterization

First Total Synthesis of a Fluorinated Calystegin

2010 ◽  
Vol 65 (4) ◽  
pp. 445-451 ◽  
Author(s):  
René Csuk ◽  
Erik Prell ◽  
Stefan Reißmann ◽  
Claudia Korb
Keyword(s):  
Total Synthesis ◽  
Ring Opening ◽  
Competitive Inhibitor ◽  
Ring Closure ◽  
Target Compound ◽  
Metathesis Reaction ◽  
Grubbs Catalyst ◽  
Ring Opening Reaction ◽  
Ultrasound Assisted ◽  
Key Steps

A straightforward chiral pool synthesis for the first fluorinated calystegin is described. Key steps of this synthesis include an ultrasound-assisted Zn-mediated tandem ring opening reaction followed by a Grubbs’ catalyst-mediated ring closure metathesis reaction. The target compound is a selective and competitive inhibitor for a β -glycosidase.

ChemInform Abstract: Synthesis of Functionalized Cyclophanes by Ring-Opening/Ring-Closure Cascade Reactions of Siloxycyclopropanes.

ChemInform ◽  
2010 ◽  
Vol 30 (21) ◽  
pp. no-no
Author(s):  
Astrid Ullmann ◽  
Margit Gruner ◽  
Hans-Ulrich Reissig
Keyword(s):  
Ring Opening ◽  
Cascade Reactions ◽  
Ring Closure

Synthesis and characterization of aluminum complexes based on amino-benzotriazole phenoxide ligand: luminescent properties and catalysis for ring-opening polymerization

2012 ◽  
Vol 26 (10) ◽  
pp. 518-527 ◽  
Author(s):  
Wan-Ju Tai ◽  
Chen-Yu Li ◽  
Pei-Hua Lin ◽  
Jia-Ying Li ◽  
Ming-Jen Chen ◽  
...  
Keyword(s):  
Ring Opening ◽  
Luminescent Properties ◽  
Ring Opening Polymerization ◽  
Synthesis And Characterization ◽  
Aluminum Complexes

ChemInform Abstract: Ring Opening Ring Closure Reactions with 3-Substituted Chromones under Nucleophilic Conditions

ChemInform ◽  
2015 ◽  
Vol 46 (50) ◽  
pp. no-no
Author(s):  
Magdy A. Ibrahim ◽  
Nasser M. El-Gohary ◽  
Sara Said
Keyword(s):  
Ring Opening ◽  
Ring Closure

scholarly journals Synthesis and Characterization of a 1,3-Phenylene-Bridged N-Alkyl Bis(benzimidazole) CCC-NHC Pincer Ligand Precursor: Homobimetallic Silver and Rhodium Complexes and the Catalytic Hydrosilylation of Phenylacetylene

2012 ◽  
Vol 32 (1) ◽  
pp. 63-69 ◽  
Author(s):  
Aron J. Huckaba ◽  
T. Keith Hollis ◽  
Tyler O. Howell ◽  
Henry U. Valle ◽  
Yunshan Wu
Keyword(s):  
Synthesis And Characterization ◽  
Rhodium Complexes ◽  
Pincer Ligand ◽  
Catalytic Hydrosilylation
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