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

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.

Anahtar Kelimeler:

Metal karboniller, Piridin, Fotokimyasal sentez

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

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,

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