• Fibers and Polymers
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• v.1 no.2
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• pp.111-115
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• 2000

The effects of nitrile group substitution onto aromatic polyamide backbone on the gas permeability and permselectivity of the polymers are examined. The gas permeability of aromatic polyamides increase with increasing the content of nitrile group substitution, whereas the permselectivity decreases with increasing the nitrile group contents. The effects of chain linrearity on the permeability and permselectivity are also examined. The non-linearity of the polymers increases the permeability. These behaviors are interpreted in terms of chain packing and crystallinity of the aromatic polyamides.

• Microbiology and Biotechnology Letters
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• v.17 no.5
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• pp.429-435
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• 1989

A bacterial strain of Brevibaterium sp. CH1 was isolated and used to produce an enzyme (nitrile hydratase) necessary for earring out the bioconversion of acrylonitrile to acrylamide. The culture and reaction conditions, and medium optimization were studied for the strain. The conversion yield was nearly 100％ with a trace amount of acrylic acid produced. The strain showed strong activity of nitrile hydratase toward acrylonitrile and extremely low activity of the amidase toward acrylamide. We sought optimum culture conditions for the formation of nitrile hydratase by Brevibacterium sp. CH1. The effects of temperature and pH on the activity of free and immobilized tells were investigated. The nitrite hydratase of Brevibacterium sp. CH1 acted not only on various aliphatic nitrites such as acrylonitrile, propionitrile and acetonitrile, but also on aromatic nitrile as nicotinonitrile.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.281-283
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• 1993

Aromatic nitro compounds are selectively hydrogenated to the corresponding amines in high yields at room temperature and atmospheric pressure using BER-Pd catalyst without affecting ketone, ether, ester, nitrile or chloro groups also present. Especially the nitro group in 4-nitrobenzyl alcohol, methyl 4-nitrobenzyl ether and N-N-dimethyl 4-nitrobenzylamine is selectively hydrogenated with this catalyst to give the corresponding amines without hydrogenolysis of benzylic groups. And aromatic nitro compound can be reduced selectively in the presence of aliphatic nitro compound.

• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.175-179
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• 2012

• Bulletin of the Korean Chemical Society
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• v.27 no.3
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• pp.432-434
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• 2006

• Bulletin of the Korean Chemical Society
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• v.7 no.4
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• pp.296-298
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• 1986

Carboxylic acid anhydrides are rapidly reduced with borane-lithium chloride (1:0.1) system to give corresponding alcohols (diols in the case of cyclic anhydride) quantitatively in tetrahydrofuran at room temperature. This reagent tolerates aromatic acid ester, nitro, and halide functional groups, however competitively reduces aliphatic ester and nitrile groups.

• Applied Chemistry for Engineering
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• v.26 no.2
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• pp.128-131
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• 2015

Hydration of nitriles in the environmentally benign neutral conditions is the most economical and attractive way to produce amides. Substantial research works have been carried out to apply the solid metal oxides and transition metal supported catalytic systems to promote the hydration of nitriles. The most significant feature of these catalysts is the applicability to a wide range of substrates including aromatic, alicyclic, hetero-atomic, and aliphatic nitriles. These catalysts are also characterized by the easy isolation from the reaction mixture and the reusability while maintaining the high catalytic activity. This review accounts over the detailed survey of the metal oxide and solid supported metal catalysts for preparing amides from the hydration of nitriles.

• Applied Chemistry for Engineering
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• v.25 no.2
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• pp.215-221
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• 2014

A simple heterogeneous system has been developed by using base treated manganese dioxide (B-$MnO_2$) for the aerobic oxidation of amines under mild reaction conditions of 1 atm of air and $50^{\circ}C$ in hexane. This system was highly efficient to oxidize various kinds of primary or secondary amines including aliphatic, aromatic, and hetero-atomic ones under the applied reaction conditions. Amines were oxidized to nitriles or diimines by the self-condensation or oxidative dehydrogenation through imine intermediate. The B-$MnO_2$ was reused for at least 5 times without any loss of its catalytic performance and showed its cost effectiveness, easy workup, and easy separation of the products for achieving the protocol of green chemistry.

• Journal of the Korean Chemical Society
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• v.17 no.4
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• pp.275-285
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• 1973

The addition of one mole of aluminum chloride to three moles of sodium borohydride in tetrahydrofuran gives a turbid solution with enormously more powerful reducing properties than those of sodium borohydride itself. The reducing properties of this reagent were tested with 49 organic compounds which have representative functional groups. Alcohols liberated hydrogen immediately but showed no sign of hydrogenolysis of alkoxy group. Aldehydes and ketones were reduced rapidly within one hr. Acyl derivatives were reduced moderately, however, carboxylic acids were reduced much more slowly. Esters, lactones and epoxides were reduced readily than sodium borohydride or borane. Tertiary amide was reduced slowly, however, primary amide consumed one hydride for hydrogen evolution but reduction was sluggish. Aromatic nitrile was reduced much more readily than aliphatic nitrile. Nitro compounds were inert to this reagent but azo and azoxy groups were slowly attacked. Oxime was reduced slowly but isocyanate was only partially reduced. Disulfide and sulfoxide were attacked slowly but sulfide and sulfone were inert. Olefin was hydroborated rapidly.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.207-207
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• 2011

Aromatic nitriles possess versatile utilities and are indispensible not only in organic synthesis but also in chemical industry. In fact, the nitrile group is an important precursor for various functional groups such as aldehydes, amines, amidines, tetrazoles, amides, and their carboxyl derivatives. Representative methods for the preparation of organonitriles with cyanide-containing reagents are the Sandmeyer and Rosenmund-von Braun reactions. Recently, a catalytic route to aryl nitriles has been reported on the basis of the chelation-assisted C-H bond activation or metal-catalyzed cyanation of haloarenes. In those cyanation protocols, the "CN" unit is provided from metal-bound precursors of MCN (M=Cu, K, Na, Zn), TMSCN, or K3Fe(CN)6. Additionally, it can be generated in situ from nitromethane or acetone cyanohydrin. Herein, we report the first example of generating "CN" from two different, readily available precursors, ammonia and N,N-dimethylformamide (DMF). In addition, its synthetic utility is demonstrated through the Pd-catalyzed cyanation of arene C-H bonds.