scholarly journals A facile synthetic route to benzimidazolium salts bearing bulky aromatic N-substituents

2015 ◽  
Vol 11 ◽  
pp. 1656-1666 ◽  
Author(s):  
Gabriele Grieco ◽  
Olivier Blacque ◽  
Heinz Berke
Keyword(s):  
Imidazole Ring ◽  
Triethyl Orthoformate ◽  
Ring Closure ◽  
Synthetic Route ◽  
Benzimidazolium Salts ◽  
Work Up

An atom-economic synthetic route to benzimidazolium salts is presented. The annulated polycyclic systems: 1,3-bis(2,4,6-trimethylphenyl)-1H-benzo[d]imidazol-3-ium chloride (1-Cl), 1,3-bis(2,6-diisopropylphenyl)-1H-benzo[d]imidazol-3-ium chloride (2-Cl), 1,3-diphenyl-1H-benzo[d]imidazol-3-ium chloride (3-Cl), and 1,3-di(pyridin-2-yl)-1H-benzo[d]imidazol-3-ium chloride (4-Cl) were prepared in a two-step synthesis avoiding chromatographic work-up. In the key step triethyl orthoformate is reacted with the correspondingN1,N2-diarylbenzene-1,2-diamines and then further transformed in situ, by alkoxy abstraction using trimethylsilyl chloride (TMSCl), and concomitant imidazole ring closure.

Synthesis of sandwich type acyclic tetra-nuclear silver(I)-N-heterocyclic carbene complexes for wound healing applications

2020 ◽  
Vol 75 (9-10) ◽  
pp. 369-376
Author(s):  
Ayesha Riaz ◽  
Muhammad Adnan Iqbal ◽  
Haq Nawaz Bhatti ◽  
Muhammad Shahid
Keyword(s):  
Alkyl Halides ◽  
Wound Contraction ◽  
Spectroscopic Techniques ◽  
Open Chain ◽  
Standard Drug ◽  
Sandwich Type ◽  
Benzimidazolium Salts ◽  
Multistep Reaction

AbstractTwo meta-xylyl linked tetrakis-benzimidazolium salts (L1-L2) as multidentate ligands and two respective silver complexes (C1 and C2) were synthesized. A multistep reaction was done at room temperature, starting with simple benzimidazole and alkyl halides, going through precursors and salt formation by reflux and finally in situ deprotonation of tetrabenzimidazolium salts with Ag2O to yield respective tetra-nuclear Ag(I)-N-heterocyclic Carbene (NHC) complexes. Propyl and butyl groups were bonded at the terminal positions of tetra-azolium open chain salts. Characterization of compounds was done by analytical and spectroscopic techniques. On the basis of spectroscopic data, a chemical structure with open chains having four Ag(I) ions sandwiched between NHC layers was established. Potential of synthesized complexes (C1 & C2) for wound contraction was evaluated and compared with standard wound contraction gel. Percentage wound contraction of both complexes was found very close to that of standard drug used in parallel.

Fabrication of a Metal Nanoparticles and Polymer Nanofibers Composite Material by an in Situ Chemical Synthetic Route

Langmuir ◽  
2005 ◽  
Vol 21 (17) ◽  
pp. 7964-7967 ◽  
Author(s):  
Kaushik Mallick ◽  
Mike J. Witcomb ◽  
Andy Dinsmore ◽  
Mike S. Scurrell
Keyword(s):  
Composite Material ◽  
Metal Nanoparticles ◽  
Synthetic Route ◽  
Polymer Nanofibers

ChemInform Abstract: A Versatile Synthetic Route to Dehydrobenzoannulenes via in situ Generation of Reactive Alkynes.

ChemInform ◽  
2010 ◽  
Vol 32 (31) ◽  
pp. no-no
Author(s):  
Michael L. Bell ◽  
Ryan C. Chiechi ◽  
Charles A. Johnson ◽  
David B. Kimball ◽  
Adam J. Matzger ◽  
...  
Keyword(s):  
Synthetic Route ◽  
In Situ Generation

Enamines in Heterocyclic Synthesis: A Novel Simple and Efficient Route to Condensed Pyridazines

2011 ◽  
Vol 66 (6) ◽  
pp. 597-602
Author(s):  
Elham S. Darwish ◽  
Mahmoud A. Abdelrahman ◽  
Abdellatif M. Salaheldin
Keyword(s):  
Hydrazine Hydrate ◽  
Triethyl Orthoformate ◽  
Heterocyclic Synthesis ◽  
Active Methyl ◽  
Efficient Route ◽  
Pyridazinone Derivatives

An efficient and easy preparation of enamine derivatives, via active methyl and methylene compounds by in situ-generated 1-(diethoxymethyl)piperidine, produced from the mixture of triethyl orthoformate/piperidine/DMF, are described. Some new pyridazinone derivatives have been synthesized from the reaction of enamines with hydrazine hydrate and cyanoacid hydrazide.

scholarly journals Reactions of 3-(p-substituted-phenyl)-5-chloromethyl-1,2,4-oxadiazoles with KCN leading to acetonitriles and alkanes via a non-reductive decyanation pathway

2018 ◽  
Vol 14 ◽  
pp. 3011-3017
Author(s):  
Akın Sağırlı ◽  
Yaşar Dürüst
Keyword(s):  
Nmr Spectra ◽  
2D Nmr ◽  
Synthetic Route ◽  
X Ray ◽  
H Nmr ◽  
2D Nmr Spectra ◽  
Tof Ms ◽  
C Nmr

The present work describes an unfamiliar reaction of 5-(chloromethyl)-3-substituted-phenyl-1,2,4-oxadiazoles with KCN affording trisubstituted 1,2,4-oxadiazol-5-ylacetonitriles and their parent alkanes, namely, 1,2,3-trisubstituted-1,2,4-oxadiazol-5-ylpropanes. To the best of our knowledge, the current synthetic route leading to decyanated products will be the first in terms of a decyanation process which allows the transformation of trisubstituted acetonitriles into alkanes by the incorporation of KCN with the association of in situ-formed HCN and most likely through the extrusion of cyanogen which could not be detected or isolated. In addition, the plausible mechanisms were proposed for both transformations. The structures of the title compounds were identified by means of IR, 1H NMR, 13C NMR, 2D NMR spectra, TOF–MS and X-ray measurements.

scholarly journals European Paediatric Surgeons' Association Survey on the Management of Pediatric Appendicitis

2018 ◽  
Vol 29 (01) ◽  
pp. 053-061 ◽  
Author(s):  
Nigel Hall ◽  
Abidur Rahman ◽  
Francesco Morini ◽  
Alessio Pini Prato ◽  
Florian Friedmacher ◽  
...  
Keyword(s):  
Abdominal Cavity ◽  
Perforated Appendicitis ◽  
Full Blood Count ◽  
First Episode ◽  
Abdominal Ultrasonography ◽  
Reactive Protein ◽  
Immediate Surgery ◽  
Evidence Based Guidelines ◽  
Work Up

Aim To define patterns in the management of pediatric appendicitis. Methods A total of 169 delegates from 42 (24 European) countries completed a validated survey administered at the EUPSA 2017 annual congress. Results In the work-up of children with suspected acute appendicitis, most surgeons rely on full blood count (92%), C-reactive protein (82%), and abdominal ultrasonography (76%), but rarely on computed tomography scans or magnetic resonance imaging. In suspected simple appendicitis, most surgeons (76%) do not perform appendectomy at night in clinically stable patients and start antibiotic preoperatively (64%), but only 15% offer antibiotic therapy alone (no appendectomy). In suspected perforated appendicitis, 96% start antibiotic preoperatively, and 92% perform an appendectomy. Presence of phlegmon/abscess is the main contraindication to immediate surgery. In case of appendix mass, most responders (75%) favor a conservative approach and perform interval appendectomy always (56%) or in selected cases (38%) between 2 and 6 months from the first episode (81%). Children with large intraperitoneal abscesses are managed by percutaneous drainage (59% responders) and by surgery (37% responders). Laparoscopy is the preferred surgical approach for both simple (89%) and perforated appendicitis (81%). Most surgeons send the appendix for histology (96%) and pus for microbiology, if present (78%). At the end of the operation, 58% irrigate the abdominal cavity only if contaminated using saline solution (93%). In selected cases, 52% leave a drain in situ. Conclusion Some aspects of appendicitis management lack consensus, particularly appendix mass and intraperitoneal abscess. Evidence-based guidelines should be developed, which may help standardize care and improve clinical outcomes.

Organic Photoredox Catalysis for Pschorr Reaction: A Metal-Free and Mild Approach to 6H-Benzo[c]chromenes

Synlett ◽  
2018 ◽  
Vol 29 (17) ◽  
pp. 2311-2315 ◽  
Author(s):  
Gaofeng Feng ◽  
Jing-Yao He ◽  
Qi-Fan Bai ◽  
Chengan Jin
Keyword(s):  
Diazonium Salts ◽  
Eosin Y ◽  
Photoredox Catalysis ◽  
Synthetic Route ◽  
Metal Free ◽  
Mild Conditions ◽  
Pschorr Reaction

An expedient organic photoredox Pschorr reaction has been developed that opens up a synthetic route to 6H-benzo[c]chromenes. The process can be performed under mild conditions by using eosin Y as a photoredox catalyst and acetonitrile as the solvent. The diazonium salts can be either preformed or generated in situ from the corresponding amines with t-BuONO. The process is amenable to gram-sale synthesis of 6H-benzo[c]chromenes, which can be further transformed into both 6H-benzo[c]chromen-6-ones through oxidation or to 6H-benzo[c]chromen-6-amine through sp3 C–H bond amination. The protocol provides an attractive route for the synthesis of a library of 6H-benzo[c]chromes.

scholarly journals One-Step Synthesis of 2-Alkenecarbodithioate Esters from Substituted Propargyl Ethers, and Their Conversion into Isothiazole Ring through a [4+1] Type Oxidative Ring Closure

2017 ◽  
Vol 12 (6) ◽  
pp. 1934578X1701200
Author(s):  
Kazuaki Shimada ◽  
Fumiya Ishikawa ◽  
Md. Ashraful Alam ◽  
Toshinobu Korenaga
Keyword(s):  
Elemental Sulfur ◽  
Ring Closure ◽  
One Step ◽  
Chloramine T ◽  
In Situ Generation

Treatment of substituted propargyl methyl ethers with a base and elemental sulfur in the presence of a thiolate ion afforded 2-alkenecarbodithioate esters in good yields. The reaction is assumed to proceed through a pathway involving in situ generation of propadienethione intermediates. Further conversion of 2-alkenecarbodithioate esters into 2,3-dihydroisothiazoles were efficiently performed by treating with chloramine-T through a [4+1] type oxidative ring closure via thiocarbonyl S-tosylimides.

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