The Malaysian Journal of Analytical Sciences Vol 16 No 2 (2012): 110 – 116

 

 

 

SYNTHESIS AND CATALYTIC ACTIVITY OF N,N’-BIS-(α-METHYL-SALICYLIDENE) – PROPANE -1,3- DIAMINEPALLADIUM(II)  AND ITS 4-METHYL DERIVATIVES IN HECK CARBON-CARBON COUPLING REACTION

 

(Sintesis dan Aktiviti Pemangkinan N,N’-Bis-(α-Metilsalisilidina-Propan-1,3-Diamina-palladium(II) dan Terbitan 4-Metil dalam Tindak Balas Gandingan Karbon-Karbon Heck)

 

Siti Kamilah Che Soh^1,2, Mustaffa Shamsuddin¹*, Bohari M. Yamin³

 

¹Department of Chemistry, Faculty of Science,

Universiti Teknologi Malaysia, 81310 Skudai, Johor, Malaysia.

²Department of Chemical Sciences, Faculty of Science and Technology,

Universiti Malaysia Terengganu, 21030 Kuala Terengganu, Terengganu, Malaysia.

³School of Chemical Sciences and Food Technology, Faculty of Science & Technology,

Universiti Kebangsaan Malaysia, 43650 Bangi, Selangor, Malaysia.

 

*Corresponding author: mustaffa@kimia.fs.utm.my

 

 

Abstract

Carbon-carbon bond formation is an important step in organic synthesis. Palladium(II) complexes have been widely used as catalyst in the transition metal catalysed bond formation. This paper reports the synthesis, characterization and catalytic performance of two palladium(II)-Schiff base complexes obtained from the condensation of 2’-hydroxyacetophenone and its 4’-methyl derivative with 1,3-diaminopropane followed by complexation with palladium(II) acetate, Pd(OAc)₂. Ligands and complexes were characterized by NMR and FTIR spectroscopic methods as well as X-ray crystallographic analysis and CHN elemental analyses. The ligands acted as N,N,O,O tetradentate, coordinating to the palladium atom through both its imine nitrogens and phenolic oxygens. The efficiency of these palladium complexes were evaluated as catalysts in the Heck reaction of 4’-bromoacetophenone with methyl acrylate in the presence of sodium hydrogen carbonate as base in N,N-dimethylacetamide as solvent at reflux temperature 120 ºC. The activities of the catalysts were monitored by GC-FID. Both catalysts gave 100% conversion after 12 hours. The product of the reactions is 3-(4-Acetylphenyl)-acrylic acid methyl ester.

 

Keywords: Palladium, Schiff base, Heck reaction

 

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