Chemical transformations of cellulose

Гальбрайх, Л. С.; Rogovin, Z. A.

doi:10.1007/3-540-06649-7_3

Cited by 9 publications

(4 citation statements)

References 13 publications

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“…21 The reaction proceeds to high yields under essentially neutral conditions.21 A similar approach was used for 6-halogeno-6deoxycellulose preparations with N-halosuccinimides where secondary hydroxyls were protected during the reaction. 22 Apart from this report, no systematic use of these reagents appears to have been made in polysaccharide modifications. Boger et alP have, nevertheless, successfully employed PI13P with carbon tetrabromide in the presence of L1N3 to prepare 6-azido-6-deoxy-a-and j8-cyclodextrins Preparation of Amylose Derivatives Modified at C-6 2921 Figure 4.…”

Section: Resultsmentioning

confidence: 93%

Preparation of Amylose Derivatives Selectively Modified at C-6. 6-Amino-6-deoxyamylose

Cimecioglu¹,

Ball²,

Kaplan³

et al. 1994

Macromolecules

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The synthesis of various amylose derivatives selectively modified at C-6 leading to the preparation of 6-amino-6-deoxyamylose (4) was carried out under homogeneous conditions. Amylose was initially halogenated directly at the primary carbon either by using methanesulfonyl chloride in dimethylformamide/ lithium chloride as solvent, giving 6-chloro-6-deoxyamylose (1) or with triphenylphosphine and Nbromosuccinimide in dimethylformamide/lithium bromide, giving 6-bromo-6-deoxyamylose (2). Several of these derivatives with different degrees of substitution were prepared. C-6 chlorinated amyloses were then converted to the corresponding 6-azido-6-deoxyamylose analogs (3) by chloride displacement with azide ion in dipolar aprotic media. Triphenylphosphine facilitated reduction of these intermediates in dimethyl sulfoxide gave 6-amino-6-deoxyamyloses with the same degrees of substitution as the C-6 chlorinated precursors. Products were characterized in terms of the site and the extent of modifications using 13C NMR, FTIR, HPLC, and elemental analyses.

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Section: Resultsmentioning

confidence: 93%

Preparation of Amylose Derivatives Selectively Modified at C-6. 6-Amino-6-deoxyamylose

Cimecioglu¹,

Ball²,

Kaplan³

et al. 1994

Macromolecules

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“…It cleaves the C2−C3 bond of the anhydroglucose unit and gives two aldehyde groups per glucopyranose unit. Whereas the product, so-called dialdehyde cellulose (DAC), is soluble in hot water, it stays water-insoluble at room temperature. , Because periodate oxidation proceeds from the surface of crystalline microfibrils, the choice of proper conditions can lead to the preparation of microfibrils coated with aldehyde groups. Utilizing this functionality, we examined the deposition of silver particles by the Tollens (silver mirror) reaction .…”

Section: Introductionmentioning

confidence: 99%

Quasi-One-Dimensional Arrangement of Silver Nanoparticles Templated by Cellulose Microfibrils

Kuga

Huang

2008

Langmuir

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We demonstrate a simple, facile approach to the deposition of silver nanoparticles on the surface of cellulose microfibrils with a quasi-one-dimensional arrangement. The process involves the generation of aldehyde groups by oxidizing the surface of cellulose microfibrils and then the assembly of silver nanoparticles on the surface by means of the silver mirror reaction. The linear nature of the microfibrils and the relatively uniform surface chemical modification result in a uniform linear distribution of silver particles along the microfibrils. The effects of various reaction parameters, such as the reaction time for the reduction process and employed starting materials, have been investigated by transmission electron microscopy (TEM) and ultraviolet-visible spectroscopy. Additionally, the products were examined for their electric current-voltage characteristics, the results showing that these materials had an electric conductivity of approximately 5 S/cm, being different from either the oxidated cellulose or bulk silver materials by many orders of magnitude.

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“…There are several reports on the chemical synthesis of polysaccharide derivatives having amino groups. Treatment of 2,3-anhydro derivatives of cellulose with ammonia gave a cellulose derivative substituted with an amino group at the C2 or C3 position; however, the selectivity and the degree of substitution were low …”

Section: Introductionmentioning

confidence: 99%

“…Treatment of 2,3-anhydro derivatives of cellulose with ammonia gave a cellulose derivative substituted with an amino group at the C2 or C3 position; however, the selectivity and the degree of substitution were low. 5 It was reported that the synthesis of polysaccharide-type polymers having amino groups was carried out by ringopening polymerization of 6,8-[3.2.1]oct-3-ene. The obtained polymer, poly(5,6-dihydro-2H-pyran-6,2-diyloxymethylene), was epoxidized and then the resulting epoxide was treated with ammonia to give an amino group-containing polymer.…”

Section: Introductionmentioning

confidence: 99%

Ring-Opening Polymerization of a 1,4-Anhydro Xylose Derivative Having an Azido Group and Synthesis of Stereoregular 3-Amino-3-deoxy-(1→5)-α-d-xylofuranan

Yoshida¹,

Kang²,

Hattori³

et al. 1996

Macromolecules

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A new 1,4-anhydro pentose monomer having an azido group, 1,4-anhydro-3-azido-2-O-benzyl-3-deoxy-R-D-xylopyranose (A3ABX), was synthesized by benzylation of 1,4-anhydro-R-D-ribopyranose at the C2 hydroxyl group and subsequent trifluoromethylsulfonylation at the C3 hydroxyl group, followed by SN2 replacement of the trifluoromethylsulfonyl group with the azido group with lithium azide. Ringopening polymerization of A3ABX was attempted with Lewis acid catalysts such as boron trifluoride etherate, phosphorus pentafluoride, and antimony pentachloride at different temperatures between -60 and -20 °C. Boron trifluoride etherate catalyst gave a polymer with a positive specific rotation and with a single C1 absorption at 99 ppm in the 13 C NMR spectrum, indicating that the resulting polymer had a stereoregular 1,5-R furanosidic structure. When the polymerization was carried out by antimony pentachloride at -60 °C, the polymer obtained had a negative specific rotation and the C1 absorption shifted downfield to around 107 ppm, suggesting that the polymer might be composed of a 1,5-β furanosidic unit. Reduction of the azido group to an amino group and the benzyl group to a hydroxyl group gave 3-amino-3-deoxy-(1f5)-R-D-xylofuranan. The structural analysis of the polysaccharides was performed by means of high-resolution 1 H and 13 C NMR spectroscopies including the two-dimensional spectra of H-H COSY, NOESY, and FGHMQC.

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Chemical transformations of cellulose

Cited by 9 publications

References 13 publications

Preparation of Amylose Derivatives Selectively Modified at C-6. 6-Amino-6-deoxyamylose

Preparation of Amylose Derivatives Selectively Modified at C-6. 6-Amino-6-deoxyamylose

Quasi-One-Dimensional Arrangement of Silver Nanoparticles Templated by Cellulose Microfibrils

Ring-Opening Polymerization of a 1,4-Anhydro Xylose Derivative Having an Azido Group and Synthesis of Stereoregular 3-Amino-3-deoxy-(1→5)-α-d-xylofuranan

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