Synthesis and structural characterization of trans-bis[1,3-bis(methoxy- ethyl)-4,5-bis(2,4,6-trimethylphenyl)imidazolidin-2-ylidene]dichloro- palladium(II)

A Pd(II) complex of a new N-heterocyclic carbene (NHC) ligand with bulky substituents and functionalized methoxy-donor side arms has been synthesized and characterized by elemental analyses, 1H and 13C NMR, and IR spectroscopy. Molecular and crystal structures of the title complex have been determined by single crystal X-ray diffraction. The compound crystallizes in the monoclinic space group P21/c, with a = 15.927(2), b = 8.489(2), c = 20.309(5) Å, β = 99.213(2)°, Z = 2, Dx = 1.253 g cm-3. The palladium atom is situated on an inversion center. There are several weak intramolecular C-H⋯N/O interactions. © 2007 Verlag der Zeitschrift für Naturforschung

Investigation of synthesis and some properties of the copper complexes containing imidazole ligand

The copper(II) complexes bearing tetrasubstituted imidazole derivatives containing oxygen donor as ligands (L1-6) were synthesized and characterized by spectroscopic methods, magnetic measurements, elemental and thermogravimetric analyses. The fluorescence efficiency of the ligands (L1-6) and their copper(II) complexes were investigated at r.t. in DMF solution. Theoretical calculations were performed for the copper(II) complex of L4 ligand, in this study. The molecular geometry, bond lengths, bond angles and vibrational wave numbers were calculated by using ab initio calculations based on the Hartree-Fock{HF/6-31G(d)} and the density functional theory {B3LYP/6-31G(d)} in the ground state

4,5-dihydro and disubstituted imidazolin derivatives

Tez üç bölümden oluşmaktadır. Birinci bölümde N-heterohalkalı karben ligandları ve bunların karben kompleksleri üzerindeki çalışmalar özetlenmiştir. İkinci bölümde deneysel çalışmalara yer verilmiştir. Üçüncü bölümde 4,5-dihidro ve disübstitüye imidazolin türevlerinin sentezi, karakterizasyonu ve katalitik incelemeler sunulmuştur. Metal-NHC komplekslerinin homojen katalizde yaygın bir şekilde kullanılan fosfinlere alternatif olmaları, son zamanlarda büyük ilgi çekmektedir. Çünkü katalitik koşullarda (yüksek sıcaklıkta) P-C bağı kolayca kopmakta ve P atomu havanın oksijeni ile kolayca oksitlenmektedir. Aksine, metal-NHC kompleksleri havanın nemi ve oksijenine karşı çok kararlıdır. Dolayısıyla tepkime ortamında ligant fazlasına gerek yoktur. Katalizör tasarımında etkinlik ve seçimliliği artırmak, ürünlerden katalizörün kolay ayrılmasını sağlamak ve katalizörün ömrünü uzun tutmak temel amaçtır. Bu nedenle daha kararlı ve etkin katalizörler hazırlamak amacıyla, imidazolidin halkasının C4-C5 konumlarında dihidro/sübstitüye fenil grupları ve azot atomları üzerinde işlevsel/hacimli grup içeren N-heterohalkalı karben öncüleri (3 ve 6) ve bunlardan türeyen Rh(I)- ve Pd(II) kompleksleri (8) sentezlenmiştir (Şema I ve II). İmidazolidin türü pek çok metal-NHC kompleksi Şema II deki i, iii ve iv basamaklarıyla gösterilen üç tepkimeden birisi kullanılarak hazırlanabilir. Özellikle basamak v, elektrofilik reaktiflerle elektroncazengin olefinlerin (ezo, 7) C=C bağını bölmek metal-NHC komplekslerinin sentezinde kullanılan yaygın bir metottur. Bununla beraber, bu yöntem bazı dezavantajlara sahiptir; olefinler genellikle neme ve oksijene karşı hassastırlar ve beklemekle bozunurlar. Bu nedenle ezo metodu (basamak v), kükürt türevlerinin (9a-c) ve 1,3-bis(pdimetilaminofenil) imidazolin içeren 8b.Rh kompleksinin sentezinde ezo izole edilmeden kullanılmıştır. Özellikle diğer iki metot (basamak i ve iii) üzerinde durulmuştur. Şema II. İmidazolinyum tuzları (3 ve 6) kolaylıkla kullanılabilir ve havada kararlıdır. Bunlar genellikle yüksek verimle saf olarak elde edildi. Çeşitli rodyum ve palladyum karben türevleri (8) imidazolinyum tuzlarının, LHX, (3 ve 6) deprotonasyonu ve transmetalasyon gerçekleştirilerek hazırlanmıştır. 1-9 bileşiklerine ilişkin kimyasal kaymalar, pik çoklukları ve göreceli şiddetlerin karşılaştırılması tüm sinyallerin yorumlanmasını sağladı. Ayrıca, imidazolinyum tuzları (LHX = 3 ve 6), Rh(I)- ve Pd(II)- NHC komplekslerinin (8) C-C bağ oluşum tepkimelerindeki katalitik aktiflikleri incelendi

In situ preparation of rhodium/N-heterocyclic carbene complexes and use for addition of arylboronic acids to aldehydes

(Chemical Equation Presented) The in situ prepared three component system [RhCl(COD)]2/imidazolidinium salts (2, 4) and KOBut catalyses the addition of phenylboronic acid to sterically hindered aldehydes affording the corresponding arylated secondary alcohols in good yields. Four novel 1,3-dialkylimidazolidinium (2-4) salts as NHC precursors were synthesized from N,N′-dialkylethylenediamine

Synthesis and structural characterization of two novel N-heterocyclic carbene complexes of Rh(I)

Two new N-heterocyclic carbene (NHC) ligands with p-methylphenyl and p-methoxyphenyl substituents on 4,5-positions and methoxyethyl pendants on N atoms of the imidazole ring were complexed together with cyclooctadiene and an iodide ion to Rh(I) to give 4a and 4b, respectively. The complexes were characterized by elemental analyses, NMR and IR spectroscopy. In addition, molecular and crystal structure of 4a was determined by single-crystal X-ray methods. In 4a the rhodium ion has distorted square planar coordination geometry chelating with cyclooctadiene (COD) ligand. Molecules of 4a form polymeric chains along the c axis through C-H ⋯ I hydrogen bonds. © 2007 Taylor & Francis

Synthesis, thermal, electrochemical and catalytic behavior toward transfer hydrogenation investigations of the half-sandwich RuII complexes with 2-(2′-quinolyl)benzimidazoles

A series ligands (L3-14) of derived from 2-(2′-quinolyl)benzimidazole (QuBim, L1) and 2-(2′-quinolyl)-5,6-dimethylbenzimidazole (QuDmBim, L2) which are an NN-type ligands have been synthesized and characterized with various techniques such as NMR, UV–vis, FT-IR spectroscopy, elemental analysis and X-ray diffraction. The substituted ligands derived from QuBim and QuDmBim have been used as sustaining ligands in the RuII-catalyzed transfer hydrogenation (TH) of acetophenone to secondary alcohols in the presence i-PrOH/KOH. The half-sandwich complexes (C1-14) of RuII with NN-type ligands have been synthesized by cleavage of [(η6-p-cymene)Ru(μ-Cl)]2 dimer. The resulting complexes have been characterized by NMR, UV–vis, FT-IR spectroscopy and elemental analysis. The thermal and electrochemical properties of selected complexes and ligands were investigated. © 2020 Elsevier B.V

The synthesis and reactions of novel pyrazole derivatives by 4-phenylcarbonyl-5-phenyl-2,3-dihydro-2,3-furandione reacted with some hydrazones

We report some novel pyrazole derivatives taking 4-phenylcarbonyl-5-phenyl-2,3-dihydro-2,3-furandione, 1. For this, 4-phenylcarbonyl-5-phenyl-2,3-dihydro-2,3-furandione, 1 was reacted with benzaldehyde(2-or 4-fluorophenyl)hydrazone to give 4-benzoyl-1-(2-or 4-fluorophenyl)-5-phenyl-1H-pyrazole-3-carboxylic acid 2a,b. Pyrazol derivative containing 2-fluorophenyl group 2a was converted into carboxylic chloride derivative 3a by thionyl chloride and then the compound 4a was obtained from reaction ammonia with compound 3a. In the next step, 4-benzoyl-1-(2-fluorophenyl)-5-phenyl-1H-pyrazole-3-carboxylic acid 2a was reacted with MeOH/H2SO4, EtOH/H2SO4, 2-nitrophenylhydrazine and 3-nitrophenylydrazine to give 5a,b and 6a,b pyrazol derivatives, respectively. The structures regarding all compounds synthesized were determined by the IR, NMR and elemental analysis method

Effect of low dose methotrexate on the bone mineral density of patients with plaque psoriasis

Amaç: Eklem tutulumu olmayan kronik plak tip psoriasis hastalarında kısa süreli düşük doz metotreksat (MTX) tedavisinin kemik mineral yoğunluğu (KMY) üzerine etkisini araştırmak. Gereç ve Yöntemler: Eklem tutulumu olmayan 15 (8 kadın ve 7 erkek) kronik plak tip psoriasis hastası çalışmaya dahil edildi. Tüm hastaların başlangıç ve MTX tedavisinin birinci yılındaki lomber vertebra (L2-4), femur (femur boynu ve total) ve önkol KMY’leri X-ray absorptiyometri ile ölçüldü. MTX tedavisi öncesi ve sonrası KMY’nin istatistiksel karşılaştırması için Wilcoxon test kullanıldı. Bulgular: Kısa süreli düşük doz MTX tedavisi kullanan hastaların lomber ve femur boynu KMY değerlerinde istatistiksel olarak anlamlı düzeyde azalma tespit edildi (her iki bölge için p0.05). Sonuç: Bu çalışma eklem tutulumu olmayan kronik plak tip psoriasis hastalarında kısa süreli düşük doz MTX tedavisinin trabeküler ve kortikal KMY’yi azaltabileceğini göstermektedirObjective: To investigate the effect of short-term low dose methotrexate (MTX) treatment on bone mineral density (BMD) of patients with chronic plaque psoriasis without joint involvement. Material and Methods: Fifteen patients (8 females and 7 males) with chronic plaque psoriasis without joint involvement were enrolled to the study. BMD of lumbar spine (L2-L4), femur (femoral neck and total) and forearm of all patients were measured using dual energy X-ray absorbtiometry, at baseline and after 1 year of MTX treatment. Wilcoxon test was used to detect differences in BMD of the patients before and after MTX treatment. Results: Significant decrease was found in the BMD of lumbar spine and femur neck in the patients taking short-term low dose MTX (p0.05, p>0.05 respectively). Conclusion: This study indicates that short-term low dose MTX treatment may decrease cortical and trabecular BMD in patients with chronic plaque psoriasis without joint involvement

Evaluation of bone mineral density in patients with plaque psoriasis without arthropathy

Psoriasis kronik seyirli, tekrarlayıcı, inflamatuvar ve hiperproliferatif bir deri hastalığıdır. Osteoporoz kemik mineral yoğunluğu (KMY) ve kemik matriksinin birlikte kaybı ile karakterize bir hastalıktır. Azalmış KMY osteoporotik kırıklar için major bir risk faktörüdür. Bu çalışmanın amacı, eklem tutulumu olmayan orta ve şiddetli plak tip psoriasisli hastalarda KMY'nu (Z skoru kullanılarak) araştırmaktır. Eklem tutulumu olmayan plak tip psoriasis tanısı konulan 43 hasta (12 erkek, 31 kadın ve yaş ortalaması 38.3) ve 30 sağlıklı kişi (9 erkek, 21 kadın ve yaş ortalaması 38.6) çalışmaya kabul edildi. Tüm olguların ve sağlıklı kişilerin lomber (L2-4), femur ve sol önkol KMY'ları X-ray absorptiyometri ile ölçüldü. Hastaların L2-4, femur ve sol önkol ortalama KMY değerleri ile sağlıklı kişilerin L2-4, femur ve sol önkol ortalama KMY değerleri arasında anlamlı fark tespit edilmedi (her bölge için p>0.05). Her iki grup 40 yaş altı ve üstü olarak ikişer alt gruba ayrıldı ve alt gruplar arasında yapılan karşılaştırmalarda anlamlı fark saptanmadı (p>0.05). Ayrıca menapozda olan hastaların KMY ile menapozda olan sağlıklı kişilerin KMY arasında da anlamlı fark tespit edilmedi (p>0.05). Sonuç olarak, bu çalışma eklem tutulumu olmayan orta ve şiddetli plak tip psoriasisli hastalarda kortikal ve trabeküler kemik dansitesinin etkilenmediğini göstermektedir.Psoriasis is a chronic, recurrent, inflammatory and hyperproliferative skin disease. Osteoporosis is characterized by decrease of bone mineral density (BMD) and bone matrix. Reduced BMD is a major risk factor for osteoporotic fracture. The aim of this study is to investigate BMD (using Z score) in patients with moderate and severe plaque psoriasis without arthropathy. Forty-three patients (12 males, 31 females and mean age 38.2) diagnosed as plaque psoriasis without joint involvement and 30 healthy subjects (9 males, 21 females and mean age 38.6) were included to this study. BMD was measured with dual X-ray absorptiometry at the lumbar spine (L2-4), femur and left forearm of all patients and healthy subjects. There were no significant differences in the mean BMD of L2-4, femur and left forearm between patients and healthy subjects (for each region p>0.05). Both groups were divided into two subgroups according to the age of the subjects as a younger and older than 40-year-old. No significant differences were detected in comparisons between these subgroups (p>0.05). Furthermore, we have not found significant differences in BMD between patients and healthy subjects which were postmenopausal (p>0.05). As a result, this study indicoted that cortical or trabecular bone density was not affected in patients with moderate and severe plaque psoriasis without joint involvement