9- Potentiometric investigations and effects of substituents on basicity  of some benzaldehyde, thiazoles and their derivatives with Schiff base type in acetonitrile and nitrobenzene

Murat SADIKOĞLU^a,  Selahattin YILMAZ^b,*,  Mustafa YILDIZ^b

 ^aKahramanmaraş Sütçü İmam University, Faculty of Sciences and Arts, Department of Chemistry, Kahramanmaraş, Turkey.

 ^bÇanakkale Onsekiz Mart University, Faculty of Sciences and Arts, Department of Chemistry, 17020 Çanakkale, Turkey

      ABSTRACT:

 The basicity of the 2-hydroxybenzaldehyde, 5-chloro-2-hydroxybenzaldehyde, 5-bromo-2-hydroxybenzaldehyde, 2-aminobenzothiazole, 2-aminothiazole and their derivatives with Schiff base type, namely (E)-2-[(benzo[d]thiazol-2-ylimino)methyl]phenol (1), (E)-2-[ (benzo[d]thiazol-2-ylimino)methyl]-4-chlorophenol (2), (E)-2-[(benzo[d]thiazol-2-ylimino)methyl]-4-bromophenol (3), (E)-2-[(thiazol-2-ylimino)methyl)phenol (4), (E)-4-bromo-2-[(thiazol-2-ylimino)methyl]phenol (5) and (E)-4-chloro-2-[(thiazol-2-ylimino)methyl]phenol (6) was investigated potentiometrically in acetonitrile and nitrobenzene. All compounds were given rather well-shaped and stochiometric titration curves in acetonitrile. The compounds 1, 2 and 3 yielded rather well-shaped and stochiometric titration curves in nitrobenzene, while the compounds 4, 5 and 6 did not yield any curves in the same  solvent. The effect of the basicity of substituents on basicities of these compound was investigated. The orders of the basicity of substituents are  found as 2-hydroxybenzaldehyde (1)> 5-bromo-2-hydroxybenzaldehyde (3)> 5-chloro-2-hydroxybenzaldehyde (2) and 2-hydroxybenzaldehyde (4)> 5-bromo-2-hydroxybenzaldehyde (6)> 5-chloro-2-hydroxybenzaldehyde  (5)

 *Corresponding author: Tel: +90-286-2180018-1857; Fax: +90-286-2180533                                     

 E-mail address: seletyilmaz@hotmail.com (S.Yılmaz)

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