• Applied Chemistry for Engineering
• /
• v.30 no.4
• /
• pp.509-511
• /
• 2019

Hydrazine derivatives used in fine chemicals, pharmaceuticals and cosmetics can be synthesized by reduction reaction from diazonium derivatives. The reduction method using $SnCl_2$ facilitates the reaction conversion, but the use of $SnCl_2$ is limited when residual heavy metals are issued in the final product. For the conversion of protected (2-hydroxyphenyl)diazonium derivatives into its hydrazine derivatives in Ramalin preparation process, the reduction method was developed by using $NaHSO_3$. In this study, the effect of steric hindrance according to the protected 2-hydroxygroupinphenyldiazonium derivatives was found, and linear C1~C5 alkyl groups for the hydroxy protection were preferable during the diazonium reduction reaction. Considering the economical efficiency and industrial production for the preparation of Ramalin, a variety of protecting groups were investigated. As a result, 2-(allyloxyphenyl)hydrazine was obtained with 85% yield and 99.7% purity when the hydroxy protecting group was used as an allyl group that could be easily deprotected.

• Journal of the Korean Graphic Arts Communication Society
• /
• v.12 no.1
• /
• pp.81.1-91
• /
• 1994

Irradiation of aromatic diazonium salts resulted in an effcient elimination of nitrogen, yielding substitution products. This paper was not only studies about photolysis of aromatic diazonium with double salts but also coexistence of ion and radical when they was photolysis. Photolysis of aromatic diazonium was depend on excite wave length therefore photolysis products out put different absorption intensity such other. We also confirmed coexistence of ion and radical when they was accomplished photolysis. In case of BD, there are ion decomposition process about 90 percentage, decreased ion decomposition process the other side radical`s it was becomeing increased according to excite of short-wave length.

• Journal of the Korean Chemical Society
• /
• v.16 no.5
• /
• pp.320-327
• /
• 1972

The coupling of aromatic diazonium salts with humic or nitrohumic acid, as a supplemental method of determining the structure and utilization of humic acid, were studied. The following results were obtained. 1) Humic acids have many vacan to-and p-positions in their phenol kernels. 2) Humic acids have not so many benzene kernels in their structure units. 3) When coupled with aromatic diazonium salts (such as aniline, aminonaphthalene and aminoanthraquinone derivatives), various azo-dye were obtained.

• Korean Journal of Food Science and Technology
• /
• v.6 no.2
• /
• pp.56-60
• /
• 1974

A survey of the available methods for the determination of piperine was made, and a new method, developed based upon alkaline hydrolysis at about $140^{\circ}C$ followed by colorimetric determination of the liberated piperidine. Piperidine on treatment with p-nitrophenyl diazonium fluoborate reagent gives a red colored complex which has an adsorption maximum at 530nm. The method measures the total pungency in pepper and applicaple to piperine of black pepper and oleoresin of black pepper. The advantage of the present method is that the pungent compounds can be determined in micro samples.

• Textile Coloration and Finishing
• /
• v.19 no.5
• /
• pp.37-40
• /
• 2007

The electrostatic layer-by-layer technique provides a convenient way to control the construction of ultrathin films at nano-scale ranges and can be easily obtained. It can be also applicable to fiber substrate with dye compounds. We have fabricated multilayer dye films using diazonium resin and three couplers, which are prepared by self-assembly approach. This method is based on layer-by-layer deposition using electrostatic attraction between oppositely charged ions. Beside, the diazo coupling reaction proceeded to form azo dye layer on the PET fibers the same time. The corresponding results of the multilayer films have been discussed on the level of color strength (K/S).

• Journal of the Korean Chemical Society
• /
• v.54 no.6
• /
• pp.737-743
• /
• 2010

Coupling of 5-amino-1,3-diaryl-pyrazoles 1a-c with diazonium salts of different aryl amines gave a series of novel 1,3-diaryl-5-amino-4-arylazopyrazoles 3a-l. Such compounds could be also obtained by reaction of 5-amino-1,3-diaryl-4-nitroso- 1H-pyrazoles 2a-c with different aryl amines in alkaline medium. Oxidation of azo derivatives 3a-l with cupric acetate, in dimethyl formamide and stream of air, gave 2,4,6-triaryl-2,4-dihydropyrazolo [4,3-d]-1,2,3-triazoles 4a-l. and the fluorescence properties of the cyclic triazoles were studied. Diazotization of 5-amino-1,3-diaryl-1H-pyrazoles 1a-c by sodium nitrite in ortho-phosphoric acid followed by coupling with some aryl amines gave o-aminoazo compounds 5a-f. Cyclisation of compounds 5a-f in pyridine and cupric acetate gave the corresponding triazoles 6a-f. The coupling of compounds 6a-f with different aryl diazonium salts gave compounds 7a-j. The synthesized dyes were applied to polyesters as disperse dyes and the fastness properties were evaluated.

• Proceedings of the Korean Magnestics Society Conference
• /
• 2007.05a
• /
• pp.324.2-324.2
• /
• 2007

• Biomedical Science Letters
• /
• v.4 no.1
• /
• pp.35-42
• /
• 1998

The effects of CRP purified from human ascites fluid on phagocytic activity of the human macrophage were investigated. CRP was purified using affinity chromatography including absorption on p-diazonium phosphocholine or C-polysaccharide coupled sepharose 4B and gel filtration on hydroxylapatite column chromatography. Macrophage was separated ficoll hypaque gradient density and absorption method, and then was confirmed phagocytic uptake test using latex method. CRP was able either to inhibit or to enhance phagocytic activity of human macrophage against bacteria in vitro. The effects of CRP on phagocytic activity of human macrophage were in time and dose-dependent manners. The additional sequence of reaction mixture against bacteria in vitro shows a threshold stimulus on the activation of phagocytic response upon the CRP.

• Archives of Pharmacal Research
• /
• v.10 no.1
• /
• pp.14-17
• /
• 1987

Several new imidazo [1, 2-b] pyrazole, pyrazolo [5, 1-c]-1, 2, 4-triazine and pyrazolo [5, 1-c] triazole derivatives were prepared from the reaction of 3-antipyrinyl-5-aminopyrazole or its diazonium salt with .alpha.-chloroacetyl derivatives.

• Proceedings of the Polymer Society of Korea Conference
• /
• 2006.10a
• /
• pp.200-200
• /
• 2006

Several polynorbornene or poly(norbornene-7-oxide) based functional block copolymers were synthesized by ring opening metathesis polymerization (ROMP) with good molecular weight and polydispersity control. Some representative functional groups in these polymers are a nitrobenzoyl group or ferrocene. These polymers were subjected to various chemical modification reactions to give other block copolymers that contain novel functionality such as amine, diazonium salt, and diazo groups. The resulting polymers were characterized by various techniques such as GPC, NMR, UV-VIS, AFM, and cyclovotammography (CV).