Synthesis of a Polysiloxane with High Reaction Activity

2014 ◽  
Vol 998-999 ◽  
pp. 15-18
Author(s):  
Сhao Hong Dong ◽  
Zhou Lu ◽  
Ping Zhu ◽  
Lei Wang
Keyword(s):  
Organic Synthesis ◽  
Methyl Iodide ◽  
Building Block ◽  
Nmr Spectra ◽  
Catalytic Amount ◽  
Reaction Conditions ◽  
Ir And Nmr Spectra ◽  
High Reaction ◽  
Ft Ir

A novel building block in organic synthesis, poly (4-iodobutoxylmethylsiloxane)(PIBMS) with high reaction activity was prepared by poly (hydromethylsiloxane)(PHMS), methyl iodide and tetrahydrofuran (THF) in the presence of a catalytic amount of PdCl2. The structure of PIBMS was characterized by the FT-IR and NMR spectra. The reaction conditions were optimized.

MECHANICAL PULPING: Characterization of dissolving pulp by multivariate data analysis of FT-IR and NMR spectra

2011 ◽  
Vol 26 (4) ◽  
pp. 398-409 ◽  
Author(s):  
Peter Strunk ◽  
Tommy Ö Öman ◽  
Mattias Hedenström ◽  
Bertil Eliasson ◽  
András Gorzsás
Keyword(s):  
Data Analysis ◽  
Multivariate Data Analysis ◽  
Nmr Spectra ◽  
Multivariate Data ◽  
Dissolving Pulp ◽  
Ir And Nmr Spectra ◽  
Ft Ir

scholarly journals Boric Acid Catalyzed Convenient Synthesis of Benzimidazoles in Aqueous Media

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Mohammad Reza Poor Heravi ◽  
Marjan Ashori
Keyword(s):  
Boric Acid ◽  
Nmr Spectra ◽  
Aqueous Media ◽  
Reaction Conditions ◽  
Efficient Catalyst ◽  
H Nmr ◽  
Convenient Synthesis ◽  
Ft Ir ◽  
Acid Catalyzed ◽  
C Nmr

Synthesis of benzimidazoles has been developed by theo-phenylenediamine with aldehydes using boric acid an efficient catalyst under mild reaction conditions in aqueous media. The product is applicable to aryl and heteroaryl aldehydes. This reaction led to the formation of benzimidazoles new derivatives in good yields. The FT-IR,19F-NMR,1H-NMR,13C-NMR spectra and elemental analysis confirm the structure of compounds.

scholarly journals Enhancing hydrophobicity, strength and UV shielding capacity of starch film via novel co-cross-linking in neutral conditions

2018 ◽  
Vol 5 (11) ◽  
pp. 181206 ◽  
Author(s):  
Ni Shuzhen ◽  
Jiao Liang ◽  
Zhang Hui ◽  
Zhang Yongchao ◽  
Fang Guigan ◽  
...  
Keyword(s):  
Nmr Spectra ◽  
Cross Linking ◽  
Ir And Nmr Spectra ◽  
Biodegradable Packaging ◽  
Uv Shielding ◽  
Novel Approach ◽  
Visible Wavelength Range ◽  
Ft Ir ◽  
Starch Films ◽  
Neutral Conditions

Starch films are developed as the biodegradable packaging materials to replace the petroleum-based materials in recent years. Thus, it is extremely beneficial to improve the hydrophobicity and mechanical strength of starch films, through a novel approach of co-cross-linking in neutral conditions, with glyoxal and AZC. In this work, systematic studies have been conducted to assess the performance of the co-cross-linked starch along with the control starch and starch cross-linked by glyoxal or AZC alone. Results showed that the co-cross-linked starch films exhibited significantly improved hydrophobicity and strength and the wet stress reached 1.53 MPa, compared to the control, glyoxal or AZC cross-linked starch films. More interestingly, the co-cross-linked film also demonstrated excellent UV shielding capacity and transmittance at visible wavelength range. The reaction mechanism was revealed based on the findings from UV, FT-IR and NMR spectra. This work established an innovative approach to improving the performance of starch film in neutral conditions for packaging applications.

Urea-Catalyzed Functionalization of Unactivated C–H Bonds

2020 ◽  
Author(s):  
Alex L. Bagdasarian ◽  
Stasik Popov ◽  
Benjamin Wigman ◽  
Wenjing Wei ◽  
woojin lee ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Organic Synthesis ◽  
High Energy ◽  
Acid Catalysts ◽  
Potential Utility ◽  
New Paradigm ◽  
Lewis Acid Catalysts ◽  
Reaction Conditions ◽  
Highly Active ◽  
Acidic Nature

Herein we report the 3,5bistrifluoromethylphenyl urea-catalyzed functionalization of unactivated C–H bonds. In this system, the urea catalyst mediates the formation of high-energy vinyl carbocations that undergo facile C–H insertion and Friedel–Crafts reactions. We introduce a new paradigm for these privileged scaffolds where the combination of hydrogen bonding motifs and strong bases affords highly active Lewis acid catalysts capable of ionizing strong C–O bonds. Despite the highly Lewis acidic nature of these catalysts that enables triflate abstraction from sp<sup>2</sup> carbons, these newly found reaction conditions allow for the formation of heterocycles and tolerate highly Lewis basic heteroaromatic substrates. This strategy showcases the potential utility of dicoordinated vinyl carbocations in organic synthesis.<br>

Urea-Catalyzed Functionalization of Unactivated C–H Bonds

2020 ◽  
Author(s):  
Alex L. Bagdasarian ◽  
Stasik Popov ◽  
Benjamin Wigman ◽  
Wenjing Wei ◽  
woojin lee ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Organic Synthesis ◽  
High Energy ◽  
Acid Catalysts ◽  
Potential Utility ◽  
New Paradigm ◽  
Lewis Acid Catalysts ◽  
Reaction Conditions ◽  
Highly Active ◽  
Acidic Nature

Herein we report the 3,5bistrifluoromethylphenyl urea-catalyzed functionalization of unactivated C–H bonds. In this system, the urea catalyst mediates the formation of high-energy vinyl carbocations that undergo facile C–H insertion and Friedel–Crafts reactions. We introduce a new paradigm for these privileged scaffolds where the combination of hydrogen bonding motifs and strong bases affords highly active Lewis acid catalysts capable of ionizing strong C–O bonds. Despite the highly Lewis acidic nature of these catalysts that enables triflate abstraction from sp<sup>2</sup> carbons, these newly found reaction conditions allow for the formation of heterocycles and tolerate highly Lewis basic heteroaromatic substrates. This strategy showcases the potential utility of dicoordinated vinyl carbocations in organic synthesis.<br>

Solid State Analysis and Theoretical Explorations on Polymorphic and Hydrate Forms of p-Hydroxybenzaldehyde Isonicotinichydrazone: Effect of Additives on Polymorphic Crystallization

2018 ◽  
Author(s):  
Lincy Tom ◽  
Victoria A. Smolenski ◽  
Jerry P. Jasinski ◽  
M.R. Prathapachandra Kurup
Keyword(s):  
Hirshfeld Surface ◽  
Framework Analysis ◽  
Reaction Conditions ◽  
Space Groups ◽  
Effect Of Additives ◽  
Ft Ir ◽  
Packing Arrangement ◽  
The Stability ◽  
Ir And Raman ◽  
Isonicotinic Hydrazide

The reaction of p-hydroxybenzaldehyde with an equimolar amount of isonicotinic hydrazide afforded two polymorphic and hydrate forms of p-hydroxybenzaldehyde isonicotinichydrazone (HBIH) by varying the experimental reaction conditions. The compounds are fully characterized by means of single crystal and powder diffraction methods, vibrational spectroscopy (FT-IR and Raman), thermal and elemental analysis. The compound crystallizes in three different forms in two different space groups, P21/c (form PA and PB) and Pbca (PC). The Hirshfeld surface analysis shows the differences in the relative contributions of intermolecular interactions to the total Hirshfeld surface area for the HBIH molecules. The calculated pairwise interaction energies (104-116 kJ/mol) can be related to the stability of the crystals. Energy framework analysis identifies the interaction hierarchy and their topology. The geometry and conformation of the three forms are essentially similar which differ only by packing arrangement.

Solid State Analysis and Theoretical Explorations on Polymorphic and Hydrate Forms of p-Hydroxybenzaldehyde Isonicotinichydrazone: Effect of Additives on Polymorphic Crystallization

2018 ◽  
Author(s):  
Lincy Tom ◽  
Victoria A. Smolenski ◽  
Jerry P. Jasinski ◽  
M.R. Prathapachandra Kurup
Keyword(s):  
Hirshfeld Surface ◽  
Framework Analysis ◽  
Reaction Conditions ◽  
Space Groups ◽  
Effect Of Additives ◽  
Ft Ir ◽  
Packing Arrangement ◽  
The Stability ◽  
Ir And Raman ◽  
Isonicotinic Hydrazide

The reaction of p-hydroxybenzaldehyde with an equimolar amount of isonicotinic hydrazide afforded two polymorphic and hydrate forms of p-hydroxybenzaldehyde isonicotinichydrazone (HBIH) by varying the experimental reaction conditions. The compounds are fully characterized by means of single crystal and powder diffraction methods, vibrational spectroscopy (FT-IR and Raman), thermal and elemental analysis. The compound crystallizes in three different forms in two different space groups, P21/c (form PA and PB) and Pbca (PC). The Hirshfeld surface analysis shows the differences in the relative contributions of intermolecular interactions to the total Hirshfeld surface area for the HBIH molecules. The calculated pairwise interaction energies (104-116 kJ/mol) can be related to the stability of the crystals. Energy framework analysis identifies the interaction hierarchy and their topology. The geometry and conformation of the three forms are essentially similar which differ only by packing arrangement.

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