Demir karben katalizli tepkimeler
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Dosyalar
Tarih
2013
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
İnönü Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Organometalik kimyada önemli bir ligant sınıfını oluşturan N-heterosiklik karbenler (NHCs) fosfin ligantlarından daha iyi katalitik aktivite ve seçicilik göstermektedir. N-heterosiklik karbenlerin geçiş metalleri ile oluşturdukları kompleksler homojen katalizlerde önemli bir yer tutar. Bu katalitik sistemler, çok büyük yarar sağlamasına rağmen bazı geçiş metalleri çok pahalı ve çoğu zaman toksik özelliğe sahiptir. Demir ise, düşük maliyeti, bolluğu ve düşük toksisite özellikleri ile katalizde diğer metallere ilginç bir alternatiftir. Son on yıl boyunca verimli bir katalizör olarak demirin kullanımı önemli ölçüde önem kazanmış ve verimli sonuçlar elde edilmiştir. Bu alandaki çabalar sadece organik kimyada demir katalizörünün geniş uygulama alanına yol açmamış, aynı zamanda organo-demir kimyasının hızlı gelişimine de katkı sağlamıştır. Son zamanlarda demir-NHC kompleksleri ucuz, çevre dostu ve etkili katalizör öncülleri gibi özelliklerinden dolayı büyük bir ilgi kazanmıştır. Bu nedenle çalışmamızda NHC öncülü olarak imidazolidinyum tuzları sentezlenmiş ve bunların demir kompleksleri hazırlanmıştır. Yapılan çalışmalar üç başlıkta özetlenebilir: 1) N-sübstitüye imidazolin bileşiklerinin farklı alkil halojenürlerle etkileşiminden 1,3-disübstitüye imidazolidinyum tuzları (1a-1ö) hazırlanmıştır. Bu bileşiklerin bir kısmı daha önce grubumuz tarafından sentezlenmiş yapılar olmasına rağmen bazıları ise yeni sentezlenmiştir. Yeni sentezlenen bileşiklerin (1a-1f) yapıları uygun spektroskopik yöntemlerle aydınlatılmıştır. 2) İmidazolidinyum tuzlarının baz ile etkileşiminden elde edilen NHC ler Fe(CO)2CpI kompleksi ile etkileştirilmiştir. Piano-stool yapısındaki Fe-NHC komplekslerinin (2a-2l) yapıları uygun spektroskopik yöntemlerle aydınlatılmıştır. İmidazolidinyum tuzları FeBr2 ve Fe(OAc)2 ile etkileştirilerek literatürde henüz örneği bulunmayan imidazolidinyumferrat kompleksleri elde edilmiştir. Bu bileşiklerin yapıları X-ışını yöntemi ile aydınlatılmıştır. 3) Sentezlenen demir komplekslerinin karbonil gruplarının indirgenmesi tepkimelerindeki katalitik aktiviteleri incelenmiştir.
N-heterocyclic carbenes (NHCs) that make up an important class of ligand (NHC) the organometallic chemistry show better catalytic activity and selectivity from phosphine ligands. The complexes are formed N-heterocyclic carbene with transition metals occupy an important place the homogeneous catalysis. These catalytic systems, although transition metals are too large to benefit some transition metals have very expensive and often toxic features. If iron is interesting alternative other metals the catalysis due to low cost, abundance and low toxicity characteristics. Over the last decade the use of iron as a catalyst in an efficient significantly gained importance and effective results were obtained. Efforts in this area have not led to a broad application area only iron catalysts in organic chemistry, but also contributed to the rapid development of the chemistry of organo-iron. In recent times iron-NHC complexes have gained great interest, due to cheap, eco-friendly and effective as catalyst precursors the properties. Therefore, in the present study, imidazolidinium NHC precursor salts were synthesized and their iron complexes were prepared. The studies summarized in main sections: 1) 1,3-Disubstituted imidazolidinium salts (1a-1o) were prepared from the interaction with different alkyl halides of N-substituted imidazoline compounds. Although some of these compounds previously synthesized by our group, some of these new synthesized. The structure of newly synthesized compounds (1a-1f, 1ö) were elucidated by suitable spectroscopic methods. 2) NHCs obtained by the interaction with the base of imidazolidinium salts were reacted with Fe(CO)2CpI complex. The structures of piano-stool Fe-NHC complexes (2a-2l) were elucidated by suitable spectroscopic methods The imidazolidinium ferrat complexes yet not found the literature were obtained by reacting FeBr2 and Fe (OAc)2 complexes with imidazolidinium salts. The structures of their were elucidated by the X-ray method. 3) The catalytic activities that the reduction reaction of the carbonyl groups of the synthesized iron complexes were determined.
N-heterocyclic carbenes (NHCs) that make up an important class of ligand (NHC) the organometallic chemistry show better catalytic activity and selectivity from phosphine ligands. The complexes are formed N-heterocyclic carbene with transition metals occupy an important place the homogeneous catalysis. These catalytic systems, although transition metals are too large to benefit some transition metals have very expensive and often toxic features. If iron is interesting alternative other metals the catalysis due to low cost, abundance and low toxicity characteristics. Over the last decade the use of iron as a catalyst in an efficient significantly gained importance and effective results were obtained. Efforts in this area have not led to a broad application area only iron catalysts in organic chemistry, but also contributed to the rapid development of the chemistry of organo-iron. In recent times iron-NHC complexes have gained great interest, due to cheap, eco-friendly and effective as catalyst precursors the properties. Therefore, in the present study, imidazolidinium NHC precursor salts were synthesized and their iron complexes were prepared. The studies summarized in main sections: 1) 1,3-Disubstituted imidazolidinium salts (1a-1o) were prepared from the interaction with different alkyl halides of N-substituted imidazoline compounds. Although some of these compounds previously synthesized by our group, some of these new synthesized. The structure of newly synthesized compounds (1a-1f, 1ö) were elucidated by suitable spectroscopic methods. 2) NHCs obtained by the interaction with the base of imidazolidinium salts were reacted with Fe(CO)2CpI complex. The structures of piano-stool Fe-NHC complexes (2a-2l) were elucidated by suitable spectroscopic methods The imidazolidinium ferrat complexes yet not found the literature were obtained by reacting FeBr2 and Fe (OAc)2 complexes with imidazolidinium salts. The structures of their were elucidated by the X-ray method. 3) The catalytic activities that the reduction reaction of the carbonyl groups of the synthesized iron complexes were determined.
Açıklama
Anahtar Kelimeler
N-Heterosiklik karben, Demir, Piano-stool demir kompleksi, Ferrat kompleksleri, Hidrosilasyon tepkimesi, Hidrojen-transfer tepkimesi, N-heterocyclic carbene, İron, Piano-stool iron complex, Ferrate complexes, Hydrosilation reaction, Hydrogen transfer reaction
Kaynak
WoS Q Değeri
Scopus Q Değeri
Cilt
Sayı
Künye
Gökçe, Y. (2013). Demir karben katalizli tepkimeler. İnönü Üniversitesi Fen Bilimleri Enstitüsü. 1-116 ss.
