Synthesis and Spectroscopic Analysis of Tetracarbonyl(4-tert-butylpyridine)metal(0) Complexes

Abstract

The photolysis of hexacarbonylmetal(0); M: Cr, Mo, W, complexes in the presence of a substituted pyridine ligand  (tert-butylpyridine) at 10 ºC yields the corresponding cis-tetracarbonyl(tert-butylpyridine)metal(0) complexes. These synthesized organometallic complexes are purified under high vacuum by recrystallization and their structures are investigated by using IR-,¹H- and ¹³C-NMR spectroscopies. Spectroscopic investigations reveal that the pyridine ligand bonded the central atom weakly through the sp² hybridized nitrogen atom of the ring. In addition to that the size of the substituent does not hinder the coordination of the pyridine through the central metal atom.

Keywords

• Metal carbonyls,Pyridine,Photochemical synthesis

Tetrakarbonil(4-tert-bütilpiridin)metal(0) Kompleks Bileşiklerinin Sentezi ve Spektroskopik Karakterizasyonu

Abstract

Hekzakarbonilmetal(0); M:Cr, Mo, W, bileşikleri ile sübstitüye piridin (tert-bütilpiridin) arasında, 10 ºC de yapılan fotokimyasal tepkimeler, cis-tetrakarbonil(tert-bütilpiridin)metal(0) bileşiklerini oluşturmaktadır. Sentezlenen bu organometalik bileşikler yüksek vakum kullanılarak yeniden kristallendirme yöntemi ile saflaştırılır ve yapıları FTIR-, ¹H- ve ¹³C-NMR spektroskopileriyle incelenir. Spektroskopik incelemeler sonucunda elde edilen veriler piridin ligand halkasının sp² hibritli azotundan zayıf şekilde bağladığını ortaya koymaktadır. Ayrıca, piridin halkasının 4-konumu üzerindeki sübstitüentinin boyutunun, piridin ile merkezi atomun koordinasyonunu engellemediği gösterilmiştir. 

Keywords

• Metal karboniller,Piridin,Fotokimyasal sentez

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