Bakır N-heterosiklik karben komplekslerinin sentezi, karakterizasyonu ve katalitik aktivitelerinin incelenmesi
Küçük Resim Yok
Tarih
2022
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
İnönü Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Son yıllarda pek çok araştırmacının yoğun ilgisini çeken N-heterosiklik karbenler, geçiş metali koordinasyon kimyasında vazgeçilmez ligandlar olarak ortaya çıkmıştır. Bu çalışmalar sonucunda NHC'ler organometalik kimyada ve birçok organik katalitik reaksiyonda oldukça önemli ligandlar haline gelmiştir. Kalıtsal olarak sp2-hibriti yapmış bir karbon üzerindeki ortaklanmamış elektron çiftine sahip NHC'lerin doğal olarak güçlü ?-donör yeteneği, metal merkezlerine olağanüstü bağlanma afiniteleri sağlar. Buna ek olarak, hem karben p-orbitaline ?-geri bağlaması ile elektron transferi hem de karben p-orbitalinden ?-verici olarak metale elektron transferi metal-ligand bağlanmasına katkıda bulunur. N-hetrosiklik karbenlerin güçlü ?-donör zayıf ?-alıcı özelliklerinden ötürü analogları olan fosfin ligantlarına kıyasla metal merkezinde daha yüksek elektron yoğunluğu ile sterik hacim sağlar. Bu üstün özellikleri sayesinde M-NHC kompleksleri katalitik reaksiyonlarda yüksek kararlılıkla beraber oldukça iyi katalitik performans sergiler. Organik bileşiklerin değişik metal kompleksleri varlığında organik dönüşüm rekasiyonları ile sentezi endüstri ve akademi için oldukça önemlidir. 1,2,3-triazollerin ılımlı koşullarda Cu-NHC katalizörlüğünde sentezi başta eczacılık olmak üzere pek çok alanda kullanılan sübstitüye triazollerin sentezinde oldukça önemlidir. Normal atmosfer koşullarında su içerisinde sübstitüye triazollerin Cu-NHC katalizli sentezlenmesi kullanılan katalizör ve ılımlı reaksiyon şartlarından ötürü oldukça ekonomik ve çevre dostu bir reaksiyondur. Cu-NHC komplekslerinin bu alandaki kullanımı oldukça sınırlı olduğundan bu alanda yeni nesil Cu-NHC komplekslerinin geliştirilmesi akademi ve sanai için oldukça önemlidir. Bu sebeplerden ötürü bu tez kapsamında sübstitüye genişlemiş halkaya sahip NHC öncülleri ve bu öncüllerin bakır komplekslerinin sentezi gerçekleştirilerek Huisgen 1,3-siklo katılma reaksiyonlarındaki katalitik aktiviteleri incelenmiştir.
N-heterocyclic carbenes (NHCs), which have attracted great interest of many researchers in recent years, have emerged as indispensable ligands in transition metal coordination chemistry. As a result of these studies, NHCs have become very important ligands in organometallic chemistry and many organic catalytic transformations. The inherently strong ?-donor ability of NHCs with an unshared electron pair on an inherited sp2-hybridized carbon provides exceptional binding affinities to metal centers. In addition, both electron transfer from the carbene p-orbital by ?-backbond and electron transfer from the carbene p-orbital to the metal as a ?-donor contribute to metal-ligand binding. Due to the strong ?-donor weak ?-acceptor properties of N-hetrocyclic carbenes, it provides steric hindrance with higher electron density in and around the metal center compared to its analogues, phosphine ligands. Thanks to these superior properties, M-NHC complexes exhibit very good catalytic performance with high stability in catalytic reactions. The synthesis of organic compounds by organic transformation reactions in the presence of different metal complexes is very important for industry and academia. The synthesis of 1,2,3-triazoles under mild reaction conditions via Cu-NHC catalysis is very important in the synthesis of substituted triazoles used in many fields, especially in pharmacy. Cu-NHC complex catalysedreaction of synthesis of substituted triazoles in water under normal atmospheric conditions is a very economical and environmentally friendly reaction in manner to the catalyst used and the mild reaction conditions. Since the use of Cu-NHC complexes in this field is very limited, the development of new generation Cu-NHC complexes in this field is very important for academia and industry. For these reasons, within the scope of this thesis, the synthesis of substituted ring-expanded NHC precursors and their copper complexes were carried out and catalytic activities of these Cu-NHC complexes in Huisgen 1,3-cycloaddition reactions were investigated.
N-heterocyclic carbenes (NHCs), which have attracted great interest of many researchers in recent years, have emerged as indispensable ligands in transition metal coordination chemistry. As a result of these studies, NHCs have become very important ligands in organometallic chemistry and many organic catalytic transformations. The inherently strong ?-donor ability of NHCs with an unshared electron pair on an inherited sp2-hybridized carbon provides exceptional binding affinities to metal centers. In addition, both electron transfer from the carbene p-orbital by ?-backbond and electron transfer from the carbene p-orbital to the metal as a ?-donor contribute to metal-ligand binding. Due to the strong ?-donor weak ?-acceptor properties of N-hetrocyclic carbenes, it provides steric hindrance with higher electron density in and around the metal center compared to its analogues, phosphine ligands. Thanks to these superior properties, M-NHC complexes exhibit very good catalytic performance with high stability in catalytic reactions. The synthesis of organic compounds by organic transformation reactions in the presence of different metal complexes is very important for industry and academia. The synthesis of 1,2,3-triazoles under mild reaction conditions via Cu-NHC catalysis is very important in the synthesis of substituted triazoles used in many fields, especially in pharmacy. Cu-NHC complex catalysedreaction of synthesis of substituted triazoles in water under normal atmospheric conditions is a very economical and environmentally friendly reaction in manner to the catalyst used and the mild reaction conditions. Since the use of Cu-NHC complexes in this field is very limited, the development of new generation Cu-NHC complexes in this field is very important for academia and industry. For these reasons, within the scope of this thesis, the synthesis of substituted ring-expanded NHC precursors and their copper complexes were carried out and catalytic activities of these Cu-NHC complexes in Huisgen 1,3-cycloaddition reactions were investigated.
Açıklama
Anahtar Kelimeler
Kimya, Chemistry
