A facile route to new potential helicating ligands

Abarca, Belén; Ballesteros, Rafaél; Elmasnaouy, Mostafá

doi:10.1016/s0040-4020(98)00955-7

Cited by 65 publications

(57 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…5 As we have found later that lithiation reactions of triazolopyridines 1 give better results using toluene as solvent and n-BuLi as lithiating agent, 6 we thought that in these conditions, and with 2-cyanopyridine as coreagent, we could improve the yield of 5d. However the new reaction gave, as only characterized product, the compound 5d in almost the same yield.…”

Section: Resultsmentioning

confidence: 81%

“…2,3 We have recently discovered a facile route to new potential helicating ligands 2a-d, 3a-d, 5d, and 6 from triazolopyridines 1a-d (scheme 1). 4,5 Following this study we have designed new ligands 7-10, which can be easily accessible from compound 5d if the methodology summarized above is applicable (see scheme 2). The understanding that the availability of 5d is important to success, led us to try its synthesis in an attempt to improve the reported yield.…”

Section: Introductionmentioning

confidence: 99%

“…The understanding that the availability of 5d is important to success, led us to try its synthesis in an attempt to improve the reported yield. 5 We wish to report here our results in this project, and the discovery of a new heterocyclic system, [1,2,3]triazolo [5',1':6,1]pyrido [3,2-d]pyrimidine 11, when we have tested the generality of the studied reaction. …”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Triazolopyridines 22.1 Description of new 7,9-di(2-pyridyl)[1,2,3]triazolo[5',1':6,1]pyrido[3,2-d]pyrimidines

Abarca¹,

Ballesteros²,

Chadlaoui³

2002

Arkivoc

Self Cite

View full text Add to dashboard Cite

The new heteroaromatic compounds, 7,9-di(2-pyridyl) [1,2,3]triazolo[5',1':6,1]pyrido[3,2-d] pyrimidines 11a-c, were synthesized in two steps from readily available triazolopyridines 1a-c. Regioselective lithiation of 1a-c followed by treatment with 2-cyanopyridine gave a mixture of compounds 5a-c, and 11a-c in moderate to low yields, together with gums. Similar reactions with the triazolopyridine 1d gave as the only identified compound the triazolopyridine derivative 5d.

show abstract

Section: Resultsmentioning

confidence: 81%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Triazolopyridines 22.1 Description of new 7,9-di(2-pyridyl)[1,2,3]triazolo[5',1':6,1]pyrido[3,2-d]pyrimidines

Abarca¹,

Ballesteros²,

Chadlaoui³

2002

Arkivoc

Self Cite

View full text Add to dashboard Cite

show abstract

“…Previously, we have reported that 1- [1,2,3]triazolo [1,5-a]pyridin-7-yl-4-(2H- [1,2,3]triazol-4-yl)-1,3-butadienes 1 can be synthesized together with bitriazolopyridines 2 in the lithiation reaction of [1,2,3]triazolo [1,5-a]pyridines 3, when reactions are carried out at -70 ºC in THF as solvent, and the mixture allowed to rise room temperature before hydrolysis, 2,3 (Scheme 1). We had nmr evidence that the intermediate 4 was formed, and this may undergo six-membered ring opening to give 1 or loss of hydride to give 2.…”

Section: Introductionmentioning

confidence: 99%

“…[4][5][6] In those cases azolyldiene derivatives with different geometry were found depending on nucleophile size and electronegativity. We now wish to report a study of the geometry of azolyldienes 1a,b and of new 1-(6-substituted-2-pyridyl)-4-(2H- [1,2,3]triazol-4-yl)-1,3-butadienes 8-10, obtained from compounds 1 and sulfuric acid, acetic acid, or selenium dioxide. …”

Section: Introductionmentioning

confidence: 99%

Triazolopyridines 21.1 The stereochemistry of 1-[1,2,3]triazolo[1,5-a] pyridin-7-yl-4-(2H-[1,2,3]triazol-4-yl)-1,3-butadienes and triazolo ring opening derivatives

Abarca¹,

Ballesteros²,

Elmasnaouy³

2002

Arkivoc

Self Cite

View full text Add to dashboard Cite

show abstract

Co^II Chemistry of 2,6‐Bis(2‐pyridylcarbonyl)pyridine: An Icosanuclear Co Cluster Exhibiting Superparamagnetic Relaxation

et al. 2006

Self Cite

View full text Add to dashboard Cite

High-nuclearity transition-metal complexes (clusters) are of special interest in chemistry and physics because, both in terms of size and physical properties, they bridge the gap between the microscopic and macroscopic world, and between quantum and classical systems. In terms of size, the smallest classical nanoparticles fabricated today are the same size as the largest metal clusters that are synthesized by bottom-up methods.[1] In terms of physical properties, certain transition-metal clusters exhibit single-molecule magnetism [2] at low temperatures, that is, they retain their magnetization in zero field in a manner analogous to that of classical macroscopic magnets, but at the same time they exhibit quantum tunneling of magnetization (QTM), [3] clearly a quantum property. For these reasons transition-metal clusters are of great interest from the viewpoint of fundamental research, and applications have been proposed relating to memory devices [4] and quantum computing. [5] From the structural viewpoint, while the number of polynuclear 3d-metal complexes continues to grow rapidly, some nuclearities remain rare. Icosanuclear complexes are particularly uncommon.A key factor in synthesizing such compounds is the proper use of ligands that can bind together a large number of metal ions. Di-2-pyridyl ketone ((py) 2 CO or dpk, Scheme 1) has afforded a host [6] of polynuclear clusters with a variety of transition-metal ions, including an Fe II enneanuclear singlemolecule magnet.[7] A metal-assisted nucleophilic attack by H 2 O or ROH on the carbonyl group of this ligand yields its gem-diol or hemiacetal form, respectively. Subsequent deprotonation of the hydroxy groups gives the mono-or dianion (in the case of the gem-diol form), which can adopt a large number of coordination modes and bridge up to five metal ions. [7][8][9][10] We therefore supposed that a similar ligand with a second carbonyl group could be attacked on both carbonyl groups to provide additional donor atoms. The 2,6-bis(2-pyridylcarbonyl)pyridine ligand [11] (pyCOpyCOpy or dpcp, Scheme 1) has two carbonyl groups, each bonded to two 2-pyridyl units in a way similar to that in (py) 2 CO. We thus thought that dpcp could have similar solvolysis, deprotonation, and coordination properties. Recent reports by Mak and co-workers on a series of Cu II , [12] Fe III , [13] and Cu I and Ag I [14] complexes verified this hypothesis.

show abstract

A facile route to new potential helicating ligands

Cited by 65 publications

References 10 publications

Triazolopyridines 22.1 Description of new 7,9-di(2-pyridyl)[1,2,3]triazolo[5',1':6,1]pyrido[3,2-d]pyrimidines

Triazolopyridines 22.1 Description of new 7,9-di(2-pyridyl)[1,2,3]triazolo[5',1':6,1]pyrido[3,2-d]pyrimidines

Triazolopyridines 21.1 The stereochemistry of 1-[1,2,3]triazolo[1,5-a] pyridin-7-yl-4-(2H-[1,2,3]triazol-4-yl)-1,3-butadienes and triazolo ring opening derivatives

Co^II Chemistry of 2,6‐Bis(2‐pyridylcarbonyl)pyridine: An Icosanuclear Co Cluster Exhibiting Superparamagnetic Relaxation

Contact Info

Product

Resources

About

A facile route to new potential helicating ligands

Cited by 65 publications

References 10 publications

Triazolopyridines 22.1 Description of new 7,9-di(2-pyridyl)[1,2,3]triazolo[5',1':6,1]pyrido[3,2-d]pyrimidines

Triazolopyridines 22.1 Description of new 7,9-di(2-pyridyl)[1,2,3]triazolo[5',1':6,1]pyrido[3,2-d]pyrimidines

Triazolopyridines 21.1 The stereochemistry of 1-[1,2,3]triazolo[1,5-a] pyridin-7-yl-4-(2H-[1,2,3]triazol-4-yl)-1,3-butadienes and triazolo ring opening derivatives

CoII Chemistry of 2,6‐Bis(2‐pyridylcarbonyl)pyridine: An Icosanuclear Co Cluster Exhibiting Superparamagnetic Relaxation

Contact Info

Product

Resources

About

Co^II Chemistry of 2,6‐Bis(2‐pyridylcarbonyl)pyridine: An Icosanuclear Co Cluster Exhibiting Superparamagnetic Relaxation