Furfuraldenevalinate system: Solution chemistry of denticity reduction, gas and solid phase complexing behavior

✍ Scribed by M. Sivasankaran Nair; C. Ravi Samuel Raj

• Book ID: 103835865
• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 174 KB
• Volume: 131-132
• Category: Article
• ISSN: 0167-7322
• DOI: 10.1016/j.molliq.2006.08.037

✦ Synopsis

Denticity reduction of Schiff base of 2 furfural (fural) and L-valine(val) in the presence of Co(II), Ni(II), Cu(II) and Zn(II) ions is investigated. The bidentate fural or val present in the metal coordination sphere interacts with the incoming ligand and forms a tridentate Schiff base furfuraldenevalinate of denticity three. This reduction in the denticity is due to entropy effect and that leads to the fusion of two independent rings, a strong interligand interaction. The Schiff base species identified are MAB, M(AB)B and M(AB) 2 [AB-Schiff base; A-fural; B-val; M-Co(II), Ni(II) and Zn(II)]. Cu(II) forms only MAB. The Schiff base species are formed around the neutral pH. The gas phase studies are carried out through ab initio HF/6-31G ⁎ and MP2/6-31G ⁎ methods. The Schiff base ligand AB is tridentate and it binds through furan and carboxylato oxygens and imino nitrogen. The binding relationship is carboxylato oxygens N imino nitrogen N furan oxygen. The order of binding in solution phase is Co(II) b Ni(II) b Cu(II) N Zn(II). The solid state study also confirms the above results.