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Article
Publication date: 7 November 2016

Galal H. Elgemeie and Doaa M. Masoud

This paper aims to focus on the most popular technique nowadays, the use of microwave irradiation in organic synthesis; in a few years, most chemists will use microwave energy to…

1268

Abstract

Purpose

This paper aims to focus on the most popular technique nowadays, the use of microwave irradiation in organic synthesis; in a few years, most chemists will use microwave energy to heat chemical reactions on a laboratory scale. Also, many scientists use microwave technology in the industry. They have turned to microwave synthesis as a frontline methodology for their projects. Microwave and microwave-assisted organic synthesis (MAOS) has emerged as a new “lead” in organic synthesis.

Design/methodology/approach

Using microwave radiation for synthesis and design of fluorescent dyes is of great interest, as it decreases the time required for synthesis and the synthesized dyes can be applied to industrial scale.

Findings

The technique offers many advantages, as it is simple, clean, fast, efficient and economical for the synthesis of a large number of organic compounds. These advantages encourage many chemists to switch from the traditional heating method to microwave-assisted chemistry.

Practical implications

This review highlights applications of microwave chemistry in organic synthesis for fluorescent dyes. Fluorescents are a fairly new and very heavily used class of organics. These materials have many applications, as a penetrant liquid for crack detection, synthetic resins, plastics, printing inks, non-destructive testing and sports ball dyeing.

Originality/value

The aim value of this review is to define the scope and limitation of microwave synthesis procedures for the synthesis of novel fluorescent dyes via a simple and economic way.

Details

Pigment & Resin Technology, vol. 45 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 February 2003

Galal H. Elgemeie, Maher H. Helal and Kawther A. Ahmed

Several new condensed carbocyclic arylazopyrazolo[1,5‐a]pyrimidine derivatives were obtained from 4‐arylazo‐3,5‐diaminopyrazoles as starting components. The application and dye…

Abstract

Several new condensed carbocyclic arylazopyrazolo[1,5‐a]pyrimidine derivatives were obtained from 4‐arylazo‐3,5‐diaminopyrazoles as starting components. The application and dye characteristics for the synthesized dyes are demonstrated.

Details

Pigment & Resin Technology, vol. 32 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 October 2002

Galal H. Elgemeie, Magdy K. Zahran, Emam M. Abbas and Ebtissam A. Abdel Mowla

Several new methylsulfanylpyrazolopyrimidines and methylsulfanylpyrazolotriazine derivatives containing an arylazo function were obtained. The application and characteristics for…

Abstract

Several new methylsulfanylpyrazolopyrimidines and methylsulfanylpyrazolotriazine derivatives containing an arylazo function were obtained. The application and characteristics for the synthesised dyes are demonstrated.

Details

Pigment & Resin Technology, vol. 31 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 December 2002

Galal H. Elgemeie, Maher H. Helal, Emam M. Abbas and Ebtissam A. Abdel Mowla

Several new pyridine‐2(1H)‐thione and thieno[2,3‐b]pyridine derivatives containing an arylazo function were obtained. The application and characteristics for the synthesised dyes…

Abstract

Several new pyridine‐2(1H)‐thione and thieno[2,3‐b]pyridine derivatives containing an arylazo function were obtained. The application and characteristics for the synthesised dyes are demonstrated.

Details

Pigment & Resin Technology, vol. 31 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 August 2001

Galal H. Elgemeie, Maher H. Helal and Heba M. El‐Sayed

The synthesis and chemistry of nitrogen heterocyclic azo compounds have been extensively studied. Many derivatives of this type were proved to be excellent dyes. Presents a…

1175

Abstract

The synthesis and chemistry of nitrogen heterocyclic azo compounds have been extensively studied. Many derivatives of this type were proved to be excellent dyes. Presents a systematic and comprehensive survey of all recently synthesised nitrogen heterocyclic azo dyes according to dyeing methods.

Details

Pigment & Resin Technology, vol. 30 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 18 September 2007

M.H. Helal, G.H. Elgemeie and D.M. Masoud

This paper aims to synthesize some new heterocyclic disperse azo dyes and their application in dyeing of polyester and polyamide fabrics.

Abstract

Purpose

This paper aims to synthesize some new heterocyclic disperse azo dyes and their application in dyeing of polyester and polyamide fabrics.

Design/methodology/approach

Pyrazolopyrimidine derivatives containing arylazo function by the reaction of 3,5‐ diaminopyrazole with ketene dithioacetals were prepared. The prepared dyestuffs are established using elemental analysis, IR measurements, 1H‐NMR and Mass spectra.

Findings

2,5‐diamino‐3‐arylazo‐N‐aryl‐6‐carboxamide‐7‐methylthio‐pyrazolo[1,5‐a]pyrimidine have been synthesized by the simple method. The dyed fabrics have a very good (4‐5) to excellent (5) results toward washing, perspiration, and rubbing fastness properties. The dyes are superior in terms of preparation and fastness properties.

Research limitations/implications

The disperse azo dyes used in this paper were synthesized via a step‐wise pathway leading to the new azo dyes. In addition, the variations in substituents and sites of location on the heterocyclic moiety could also be studied.

Practical implications

The new azo dye systems based on substituted pyrazolopyrimidine provided a series of azo dyes with improved dyeing properties. The dyes are superior in terms of yield, purity, colour strength, and fastness properties and will lead to valuable achievements for commercial production.

Originality/value

The synthesized disperse azo dyes are superior in terms of preparation, yield, purity, and fastness properties.

Details

Pigment & Resin Technology, vol. 36 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 8 February 2021

Ebtsam Abdelmowla Ahmed, Galal Elgemeie and Kawther Abd-Elzaher Ahmed

This study aims to represent a successful simple method for the synthesis of some novel dyes based on thiazole derivatives and their applications in textile printing.

Abstract

Purpose

This study aims to represent a successful simple method for the synthesis of some novel dyes based on thiazole derivatives and their applications in textile printing.

Design/methodology/approach

2-(benzo[d]thiazol-2-ylmethyl)thiazol-4(5H)-one compound is prepared by convention heating and microwave technique then used as a coupling agent, which reacts with different diazonium Salt to form diazo dyes.

Findings

The synthesized diazo dyes are confirmed via spectral data (IR,1H-NMR, 13C-NMR and Mass spectra). The dyes are used to print polyester fabric. The obtained results clarified that the prints have good color strength, brilliant color and highly durable antibacterial activity.

Originality/value

The authors designed efficient synthesis for some novel thiazolone dyes. The novel procedure features short-reaction time, very good yields and a simple workup. The authors studied the antibacterial activity and their application in printing polyester fabrics.

Details

Pigment & Resin Technology, vol. 51 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 11 September 2009

Zaker Bahreini

The purpose of this paper is to synthesise, characterise and find out properties of some new arylazopyridone disperse dyes, bearing different substituents on coupling component of…

Abstract

Purpose

The purpose of this paper is to synthesise, characterise and find out properties of some new arylazopyridone disperse dyes, bearing different substituents on coupling component of the dyes.

Design/methodology/approach

The dyes are synthesised by diazotisation, coupling and cyclization reactions, starting from various aryldiazonium salts and different β‐diketoesters followed by condensation with cyanoacetamide. The structures of these dyes are characterised and confirmed by melting point, elemental analysis, infrared, ultraviolet‐visible spectroscopy (UV/VIS) and nuclear magnetic resonance (1H‐NMR) data. Their absorption properties in different solvents are also investigated.

Findings

The wavelength of maximum absorptions, molar extinction coefficients are strongly dependent on the electron donating ability of the substituents on the coupling moiety. The absorption bands of these dyes move towards longer wavelength as the polarity of the solvents and electron density of substituents on the coupling moiety increase. These dyes are chromophorically strong as evidenced by molar extinction coefficient in solvents.

Originality/value

In this paper, four series of arylazopyridone dyes (21 dyes) are synthesised and characterised. They have not been registered in the literature previously.

Details

Pigment & Resin Technology, vol. 38 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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