Efficient eco-friendly syntheses of dithiocarbazates and thiosemicarbazones

• Published in: Green chemistry letters and reviews Vol. 13; no. 2; pp. 129 - 140
• Main Authors: Ali, Nur Halilatul Sadiqin O., Hamid, Malai Haniti S. A., Putra, Nurul Amirah 'Aqilah Mohamad 'Asri, Adol, Hajar Azirah, Mirza, Aminul Huq, Usman, Anwar, Siddiquee, Tasneem A., Hoq, Md. Rejaul, Karim, Mohammad R.
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 02-04-2020; Taylor & Francis Ltd; Taylor & Francis Group
• Subjects: Aromatic compounds; Carbonyl compounds; Carbonyls; Catalysts; Chemical synthesis; Crystal structure; Crystal structures; Crystals; Dithiocarbazates; Eco-friendly synthesis; Fruit juices; Imines; Lemons; Schiff bases; Single crystals; Solvents; Thiosemicarbazones; X-ray diffraction
• ISSN: 1751-8253; 1751-7192
• DOI: 10.1080/17518253.2020.1737252

Eight Schiff bases have been synthesized by conventional and three different eco-friendly methods, whereby two aromatic carbonyl compounds viz. 2-thiophenecarboxaldehyde and salicylaldehyde were reacted with S-methyl, S-benzyl, and S-n-octyl-dithiocarbazates and thiosemicarbazide. In order to evaluate the efficiency of the synthesis methods, the time to complete the reaction and the yield of the Schiff base synthezised by eco-friendly methods, such as solvent-free grinding, water as a solvent, and lemon juice as catalyst, were compared with those synthesized by the conventional method. The chemical structures of all the synthesized Schiff bases, where two of them are novel and reported for the first time, were fully characterized by a variety of physico-chemical, analytical, and spectroscopic techniques. The molecular and crystal structures of the Schiff bases especially those having 2-thiophene moiety were further elucidated by single crystal X-ray diffraction analyzes.