Design and synthesis of push–pull chromophores: Effects of conjugation types on the optoelectronic properties
Başlık çevirisi mevcut değil.
- Tez No: 403366
- Danışmanlar: Prof. Dr. FRANÇOIS DIEDERICH
- Tez Türü: Doktora
- Konular: Kimya Mühendisliği, Chemical Engineering
- Anahtar Kelimeler: Belirtilmemiş.
- Yıl: 2015
- Dil: İngilizce
- Üniversite: Eıdgenossısche Technısche Hochschule Zurıch (eth)
- Enstitü: Yurtdışı Enstitü
- Ana Bilim Dalı: Belirtilmemiş.
- Bilim Dalı: Belirtilmemiş.
- Sayfa Sayısı: Belirtilmemiş.
Özet
Özet yok.
Özet (Çeviri)
Since 2005, the Diederich group has conducted comprehensive research to develop nonplanar push–pull chromophores possessing significant optoelectronic properties (Chapter 1). Formal [2+2] cycloaddition–retroelectrocyclization (CA–RE) reactions have been utilized to accomplish this synthetic goal. In the last ten years, most of our studies have addressed the reactions of commonly used tetracyanoethene (TCNE) or 7,7,8,8- tetracyano-p-quinodimethane (TCNQ) with activated alkynes. However, there are only a few reports exploring the possibility of altering the acceptor molecule for these reactions. To tackle this issue, we introduced 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as an electron-deficient alkene moiety in formal [2+2] CA reactions (Chapter 2). Surprisingly, the chosen alkene was not suitable to undergo RE following initial CA. Attempts to force the RE instead resulted in an unexpected rearrangement whereby the spirocyclic push–pull chromophores were obtained. Although novelty of reaction is enough to justify working in this area, the optoelectronic properties of the formed push– pull chromophores have significant importance. The structural and optoelectronic properties of the chromophores were investigated by X-ray analysis, UV/Vis spectroscopy, electrochemistry, and computational analysis. Additionally, the thermal rearrangement of homoconjugated chromophores was studied by electron paramagnetic resonance (EPR) spectroscopy to confirm whether the reaction includes free radical intermediates or not. Chapter 3 describes the synthesis of sophisticated push–pull chromophores by the reaction of tetrahalo-p-benzoquinones with donor-substituted alkynes. The formed chromophores showed remarkable optoelectronic properties, such as very intense intramolecular charge-transfer (ICT) bands and solvatochromism. Further studies on these chromophores provided us key knowledge to modify previously described homoconjugated systems by post-synthetic modifications. Similar to the DDQ adducts, the optoelectronic properties of the chromophores were investigated by UV/Vis spectroscopy, electrochemistry, and computational analysis. Within the chromophore series, donor strength was varied systematically to define structure-property relationships. In the last Chapter of the thesis, we describe the demanding synthesis of a Janusdendrimer- type push–pull system (Chapter 4). A convergent, multi-step method was developed and used for the synthesis of this sophisticated structure. The target Janussystem is composed of a ferrocene (Fc)-substituted donor hemisphere and a second hemisphere with tetracyanobutadienes (TCBD)s as electron acceptors. The synthetic approach for the target Janus-dendrimer-type system is based on a Sonogashira cross-coupling of different Fc-substituted dendron structures and a [2+2] CA–RE with TCNE. The Janus system displays a broad ICT band with end-absorption reaching to the near-infrared (NIR) region. The key question was whether the two hemispheres in the Janus-system are electronically communicating with each other or not. Both UV/Vis spectral comparisons and electrochemistry results confirm that there is no communication between the hemispheres. Observed CT bands originated from independent push–pull systems in one hemisphere.
Benzer Tezler
- İzmir'de bazı yolların kapatılarak yaya bölgeleri oluşturma da kent peyzajını geliştirme açısından yeniden planlanması üzerinde araştırmalar
Başlık çevirisi yok
BAHAR TÜRKYILMAZ
Yüksek Lisans
Türkçe
1985
Şehircilik ve Bölge PlanlamaEge ÜniversitesiŞehir ve Bölge Planlama Ana Bilim Dalı
- Ağızlık açma mekanizmalarının tasarımı
Başlık çevirisi yok
RECEP EREN
Yüksek Lisans
Türkçe
1987
Tekstil ve Tekstil MühendisliğiUludağ ÜniversitesiTekstil Mühendisliği Ana Bilim Dalı
DOÇ. DR. HALİL R. ALPAY
- Sonbahar sera yetiştiriciliğine uygun hıyar çeşit seçimi
Selecting a cucumber variety suitable for glasshouse production in Autumn
MESUT OKTAY
- İki katlı pamuk ipliklerinden dokunan kumaşlarda örgüye bağlı olarak maksimum atkı sıklığının değişimi üzerinde bir araştırma
Başlık çevirisi yok
MELTEM ASLI NARTER
Yüksek Lisans
Türkçe
1985
Tekstil ve Tekstil MühendisliğiEge ÜniversitesiTekstil Mühendisliği Ana Bilim Dalı
DOÇ. DR. GÜNGÖR BAŞER
- Küçük Yamanlar tepesi örneğinde kent yakın çevresinde rekreasyon alanı düzenleme projesi
Başlık çevirisi yok
NİHAN BULGUN
Yüksek Lisans
Türkçe
1985
Şehircilik ve Bölge PlanlamaEge ÜniversitesiPeyzaj Mimarlığı Ana Bilim Dalı
DOÇ. DR. İLÇİN ASLANBOĞA
- Çukurova bölgesinde biyoklimatik veriler kullanılarak açık ve yeşil alan sistemlerinin belirlenmesi ilkeleri üzerinde bir araştırma
A research on the determination of the principles in open and green spaces systems by using the bioclimatic data in Çukurova region
MEHMET FARUK ALTUNKASA
Doktora
Türkçe
1987
Çevre MühendisliğiÇukurova ÜniversitesiPeyzaj Mimarlığı Ana Bilim Dalı
DOÇ. DR. ERDOĞAN GÜLTEKİN